The Breath of the Wild Expansion Pass includes the Trial of the Sword: a challenge that will power up the Master Sword if completed.
How to Unlock the Trial of the Sword
To unlock the Trial of the Sword, you will need to purchase the Breath of the Wild Expansion Pass, complete The Hero's Sword quest, and leave the Lost Woods. A voice will tell you to speak with the Deku Tree. When you approach the pedestal where you pulled out the Master Sword, a cutscene will occur. Afterward, you can begin the Trial of the Sword any time by putting the Master Sword back into the pedestal.
Beginning Trials: Underground Floor 1
There are three Bokoblins around a campfire. Avoid letting them see you until you have a weapon. The Bokoblins' weapons are leaning up against a log, and there is also a tree branch at the base of a tree between you and them. Push in the left control stick to crouch, then sneak around the edge of the room toward the log where their weapons are. If you see a question mark over any of their heads, run over to the weapons and grab as many as you can, then run away to avoid letting them hit you.
The weapons you can get in this room are a Woodcutter's Axe, a Boko Club, Boko Spear, and a Boko Shield, as well as the Tree Branch. You can cut trees to get more Tree Branches, but you might want to avoid using your weapons so they'll last longer.
After you kill the Bokoblins, collect the food. There is a Seared Steak over the fire, and you can break open the wooden crates for some fruits and shrooms. Throw the barrels at the wall to break them open (stand close to but not touching the wall when you throw them) and get some apples. Climb the tree in the middle of the room to get a couple of bird eggs.
Then warp to the next room.
Underground Floor 2: Beginning Trials
There is a Fire Chuchu in this room, but don't kill it yet, because it will leave a trail of flames that you can use to float up with the Paraglider if you need a quick escape.
There is a big wooden platform in the middle of the room with several Bokoblins on it. They can't actually get down from the platform, and only one of them has a bow, so you can ignore them as long as you stay out of range of the rocks they throw and the arrows that the bowman shoots.
There is a smaller platform off to the side with one Bokoblin on it, who also has a bow.
You should allow the bow-wielding Bokoblins to shoot arrows in your direction, but sidestep them so you can collect the arrows from the ground. You will want to have as many arrows as possible.
When you are ready, climb up the ladder to the smaller platform and kill the Bokoblin. Take his bow and any arrows you can get. The barrels next to this platform contain more arrows.
Now use the updraft from the fire Chuchu to float up, and shoot the Bokoblins in slow motion. Aim for their heads to do the most damage.
After you have killed all of the Bokoblins, collect all the loot. There is a Boko Bat, a Traveler's Sword, a Traveler's Shield, and the two Boko Bows.
Break open the crates to get some arrows and fruits.
Underground Floor 3: Beginning Trials
There is a Chuchu in this room. As soon as you kill it, four Fire Chuchus will appear.
There are actually two treasure chests on ledges on the outer walls of this room, so lure the Fire Chuchus there and float up to reach the chests. One chest contains five fire arrows, and the other contains a Boomerang.
When you kill the Fire Chuchus, keep in mind that they explode in flames when you kill them, so you will likely get hurt if you kill them at close range. It is safer to use your bow and arrows, or the Boomerang that you can get from one of the two ledges on the outer walls of this room.
After you kill the first four Fire Chuchus, four more will appear. After you kill those, you can continue on to the next room.
Underground Floor 4: Beginning Trials
There is a large wooden platform in the middle of the room. This one has stairs up to the top, so if any of the Bokoblins on it see you, they will run after you. And they will see you if you stand in the spot where you start the room, so try to hide behind something if you want to survey the area.
One of the Bokoblins on the tall tower will shoot fire arrows. There are a couple of Blue Bokoblins on that platform as well.
There is also a very tall platform that you can reach by ladder. At the top of this platform, there is a Bokoblin, and a few bomb barrels. It is dangerous to try to attack this Bokoblin by climbing to the top of the platform because if the bomb barrels explode while you are up there, you will die or be seriously injured. However, there are two metal crates on the large platform, so after you kill the Bokoblins there, use Magnesis to lift the crates to the top of the large platform, and from there you can hit the Bokoblin at the top of the tall platform.
Some of the equipment that you can get in this room are a Traveler's Bow, Spiked Boko Bow, Traveler's Spear, Soldier's Broadsword, and Soldier's Shield. Be sure to climb the trees to get some bird eggs, and break the crates on the platform to get some additional items.
Underground Floor 5: Beginning Trials
There are a couple of Moblins in this room. There is also a giant skull building in the middle. Stay away from the entrance of the skull building to prevent the Bokoblins inside from seeing you while you fight the Moblins.
Since the Moblins are slower-moving than Bokoblins, try attacking them from a distance. You can also run out of range of their weapons when they are preparing to swing them.
After killing the Moblins, avoid letting the Bokoblins in the skull see or hear you. One way to deal with the Bokoblins is to knock down the torches in the eyes of the skull, which will detonate some bomb barrels. Just shoot the chain, not the torch itself. However, this won't kill all of them, and it will also open up some food containers, and the Bokoblins will then eat the food if you are not quick. It will also potentially burn up the wooden weapons that those Bokoblins used. You might prefer to fight them in melee combat instead.
Some of the weapons in this room are a Spiked Boko Bat, Spiked Boko Club, Spiked Boko Spear, Moblin Spear, and Moblin Club.
Underground Floor 6: Beginning Trials
There is a Stone Talus in the middle of this room. It won't wake up until you get close to it or detonate a bomb near it. So switch to your round bombs, then throw one at the Talus and detonate it.
After it gets up, throw bombs to blow up the Talus's arms. If you miss, keep running and stay at a distance from the Talus to try to avoid its arms if it throws them at you.
As soon as you blow up one arm, run up to the Stone Talus and climb on top of it, then use your most powerful weapon and hit the crystal on top of it repeatedly. But the Talus will knock you off if you stand on it too long, injuring you, so run away from the Talus after you have hit the crystal several times.
Repeat the process until the Talus dies. It doesn't drop any items, so just warp to the next room when you're done.
Underground Floor 7: Beginning Trials
This room has no enemies, but has a cookpot and some treasure chests, and other helpful items. There is even a fairy floating around, so move very slowly so you can catch the fairy without making it run away. There are apples on a tree, and some fish in the water.
The chests contain a Serpentine Spear, Eightfold Blade, and a Shield of the Mind's Eye.
The nearby crates contain fire arrows, arrows, and some raw meat.
Be sure to cook your meat, fish, and mushrooms, because cooked ingredients restore a little more health than raw, and cooked meals have bonus effects (the Armored Carp become Tough Fish Skewers, etc.)
Underground Floor 8: Beginning Trials
In this room, there is a Lizalfos on the island where you start. It is armed with a Lizal Boomerang. There is another Lizalfos on a small stone island. It will shoot at you if it sees you. After you kill it, take its Lizal Bow. There are some small rocks near this island, and there is a metal treasure chest near those rocks underwater. Use Magnesis to pull it up. It contains arrows.
Then go over to the campfire where there are two Lizalfos. You can shoot the Electric Chuchu from a distance to shock the Lizalfos, allowing you to run in and steal their weapons (just be sure that you have enough weapon slots).
After you kill the Lizalfos, take the Roasted Bass from the campfire.
Underground Floor 9: Beginning Trials
There is an Electric Wizzrobe in this room. There is also an Octorok that will spit at you from the water. There is another Octorok farther away.
Near one corner of the room, there is a treasure chest. Use Cryonis under the chest, then open it to get some arrows.
Climb a tall rock, then float toward the Wizzrobe, and shoot at it while floating so you can hit it in slow motion.
Take the Lightning Rod that the Wizzrobe drops.
Underground Floor 10: Beginning Trials
You start on a wooden bridge, and there is a Lizalfos straight ahead that will see you as soon as you appear. There are also two Black Lizalfos. Try to fight them on the larger part of the platform so you don't fall in the water, because they swim much more quickly than you do, and they will spit water at you from a distance.
After you kill them, be sure to break the crates in the room to get some food and arrows. There are metallic crates on a wooden platform to the side that contain arrows.
Underground Floor 11: Beginning Trials
You will be in a windy room with a raft nearby. Stay at the far end of the pier to avoid letting the Bokoblins in the distance see you. When you are ready, get on the raft and cut the rope. The wind will take you close to the platforms.
Underground Floor 12: Beginning Trials
There is a Blue Hinox in this room. You can climb the palm trees here to get some palm fruit to heal up before the Hinox is walking around. There is also a metal crate underwater that contains some arrows. It might wake up the Hinox if you drop it on the ground, though.
Try to sneak up to the Hinox's face and shoot its closed eye with an arrow, then when it gets up and falls down, attack it with your strongest weapon. Be aware that it has leg armor, so you won't be able to hurt its legs while it is walking around. Try to shoot its eye as it walks around, but it will cover its eye sometimes. You might need to just keep shooting at it to slowly chip away at its HP. You also will get an opening to hit its eye if it is about to pick up a tree.
When the Hinox dies, it drops a Knights Bow, Knights Shield, and Knight's Broadsword.
Power Up Master Sword
After this, you will be in a special room where the Sword Monk will tell you to pull the Master Sword. After you do, the Master Sword's power will increase to 40 and you will return to Korok Forest, where you can save the game.
After you have completed the Beginning Trials, you can put the Master Sword into the pedestal again and select Middle Trials to start the next set of trials.
Middle Trials: Underground Floor 1
Jump and press X to float up with the Paraglider. The whole room has an updraft, so you don't have to jump over the bottomless pit to start floating.
There is a ledge to the right with no enemies on it where you can get a Boko Spear. There are some wooden crates as well. Stand near the wooden crates, but turn around and look at the Bokoblin that has fire arrows. When he is about to shoot, run out of the way of the wooden crates. The fire from his fire arrows will burn up the crates. One of the crates contains some mushrooms.
Next, float to the ledge directly across from where you got the Boko Spear. There is a Bokoblin with a Woodcutter's Axe and a Bokoblin with a Boko Bow. There is also a Boko Club leaning against the wall near a bomb barrel. After you kill the Bokoblins and take their weapons, throw the two wooden barrels while standing close to, but not up against, a wall, and you will get some arrows.
Try using Magnesis to drop a metal box on the Bokoblin that is shooting fire arrows from the other ledge. It should kill that Bokoblin.
Then float to the center ledge. You can kill the Bokoblins in slow motion by shooting while floating (aim at their heads to do the most damage), or just land on the platform and kill them in melee combat.
They drop a Spiked Boko Spear, Spiked Boko Club, and Spiked Boko Shield. Break the wooden barrels to get more arrows, then use your Woodcutter's Axe on the wooden crates to get some fruit and some fire arrows.
Before you go, use the Paraglider to float up over the ledge with the warp point on it. There is a platform that has a Soldier's Bow on it. If you can't reach it, try falling a short distance, then pulling out the Paraglider again. You will go a little higher up than the updraft normally takes you. Or you can just shoot the platform with a fire arrow.
There is another platform with a treasure chest on it over one of the side ledges. Use the Sheikah Sensor to find it. You will need the fire arrows from the wooden crates near the warp point. Float up to the treasure chest, then shoot a fire arrow at the leaves under the platform. Fall and glide down to the treasure chest and open it to get a Soldier's Broadsword.
Underground Floor 2: Middle Trials
Just like the previous room, this one has an updraft everywhere. Kill the Bokoblins on the starting ledge to get a Soldier's Spear, a Soldier's Broadsword, and a Soldier's Shield. Afterward, break the wooden crates on this floor to get some raw meat and some mushrooms.
Float one ledge up from the current one to find another Bokoblin. This one has a Spiked Boko Bow. After you kill it, break the wooden crates to get more arrows.
The only remaining enemies in this room are the Fire Wizzrobe and the Meteo Wizzrobe. Use the updraft to shoot at their faces while you float. However, if you want to get their Fire Rod and Meteo Rod, you have to be careful not to shoot them in the face if they are not above a ledge. Otherwise they will fall into the bottomless pit and die. But the Meteo Wizzrobe has a lot of HP, so it will use up a lot of your ammo and damage your weapons a lot if you try to kill it, so you might just want to shoot it in the face and make it fall into the bottomless pit. The Meteo Wizzrobe can also cast a meteor spell that makes fireballs constantly fall from the sky. It also heats up the room so much that you will periodically take damage from the heat.
There is a Feathered Edge sword in a treasure chest in the corner of the room. You will need to set the wooden platform on fire to be able to get the chest. Then you can go to the next room.
Underground Floor 3: Middle Trials
The Bokoblins on the far ledge will see you soon after you arrive and start shooting Bomb Arrows at you. You can either float to that ledge and kill the Bokoblins there who have bows, or you can try to quickly shoot down the floating platform that have a Bokoblin on it, to try to prevent him from seeing you and blowing his horn.
After killing the bomb arrow Bokoblins and the other Bokoblin on their ledge, collect any loot you find on that ledge, including a Lizal Forked Boomerang, and a Reinforced Lizal Shield. The barrels and crates have arrows, bomb arrows, and food.
Then try to kill the Bokoblin who is shooting ice arrows at you, and float to his ledge afterward to break open the crates, which contain food, and ice arrows.
Finally, kill the Bokoblins on the other ledge to get some arrows, shock arrows, an Enhanced Lizal Spear, and a Boko Bow.
Before you leave, go to the ledge below the other floating platform (if it hasn't been shot down), and shoot the balloon closest to the ledge to make the treasure chest fall down to the ledge. Open it to get a Feathered Spear.
Underground Floor 4: Middle Trials
A Decayed Guardian across from where you entered the room will see you right away. It is the only enemy in the room. Float to it as soon as possible and shoot it in the eye to temporarily stun it. With luck, you will prevent it from shooting. Then float to its platform, shooting it in the eye again to stun it longer. Hit it repeatedly with your most powerful weapon, but be sure to shoot it in the eye periodically to prevent it from shooting you.
Afterward, break all of the crates in the room. There is a floating metallic chest in a corner of the room. Shoot the balloons, but try to use Magnesis to keep the chest in the corner so it won't fall into the pit. The chest contains a Knight's Shield.
There is also a chest on a wooden ledge. Burn the ledge with a fire arrow. The chest contains a Soldier's Bow.
Underground Floor 5: Middle Trials
There are no enemies in this room. Move slowly so you can catch the fairy that is floating around. Then open the chests to get a Falcon Bow, Hylian Trousers, and a Knight's Broadsword.
Break the crates to get arrows and food.
There is a Woodcutter's Axe leaning against a tree.
There is a torch near the cook fire, and there are mushrooms and apples that you can gather, as well as a few Hyrule Bass you can catch. Be sure to cook everything, but not the fairy. The fairy will revive you if you die, but if you cook it, the resulting tonic can't revive you if you die.
Underground Floor 6: Middle Trials
In this dark room, some Fire Keese will fly toward you. Kill them before they can hit you. Then shoot the Electric Chuchu from a distance so it can't shock you when it dies. There are also some Fire Keese sleeping in the tree up ahead. Shoot them down with arrows.
After you kill all of the enemies in the room, the lights turn on. There aren't any items to collect in this room (that I know of), so continue on to the next room.
Underground Floor 7: Middle Trials
There are several Lizalfos in this dark room, including one inside of the skull that will shoot fire arrows. If any Lizalfos engage you in melee combat, try to stay close to them and hit them before they can hit you. You can shoot the rope of the torches in the eyes of the skull to detonate the bomb barrels inside, killing or at least injuring the Lizalfos inside that shoots fire arrows.
The lights come on after you kill all of the enemies. Be sure to hurry into the skull to collect any wooden weapons inside that may have caught fire, such as a Forest Dweller's Spear. You can also find meat and arrows, and a Strengthened Lizalfos Bow, in the skull. Be sure to pick up the Flameblade that one of the Lizalfos was wielding. Then move on to the next room.
Underground Floor 8: Middle Trials
In this dark room, there are Bokoblins around a fire. There is also a Meteo Wizzrobe. At this point, you should have a few ice arrows, so use them carefully to instantly kill the Meteo Wizzrobe. Then try to hide behind walls to stealthily kill the Bokoblins.
Gather any weapons and items from the room that you want, then continue on.
Underground Floor 9: Middle Trials
There is only one enemy in this room: a Decayed Guardian. From where you start, you should be able to hide behind the wall and shoot at the Decayed Guardian without it being able to see you. Use your strongest bow and aim at its head to do the most damage.
After it's gone, be sure to break the wooden crates on one of the stone structures to get more arrows.
Underground Floor 10: Middle Trials
There is a Blue Hinox asleep in the middle of the area. It has 800 HP. Before you wake it up, its legs will be pointing toward where you entered the room. Use a torch to sneak up to the Hinox and see where its wooden leg armor is. Then light its leg armor on fire with the torch, or shoot at its legs with the Meteor Rod.
It drops a Thunderstorm Rod and a Knight's Broadsword. There is a Rusty Claymore and Rusty Halberd in this room. Be sure to break the wooden barrels to get arrows. You can also get a new torch here.
Underground Floor 11: Middle Trials
There are no enemies in this room. Sneak up to the fairies so you can catch them. The chests contain a Forest Dweller's Sword, a Hylian Tunic, and a Forest Dweller's Spear.
Underground Floor 12: Middle Trials
This room is filled with Guardian Scout Is. Equip your weakest shield, hold the shield up by holding ZL, then press A just before the Guardian Scout beams hit you. You will deflect the beam back at the Guardian Scout, killing it.
Before you go, use Cryonis to reach the chest on the ledge. Open the chest to get arrows.
Underground Floor 13: Middle Trials
There are Guardian Scout IIs in this room. Do backflips and sidesteps to dodge them right before they hit you. If you do it correctly, you can do a flurry rush. These enemies drop a Guardian Sword, Guardian Spear, and an Ancient Battle Axe.
Before you go, use Magnesis to find the secret panel that has a treasure chest behind it. The chest contains a Duplex Bow.
Underground Floor 14: Middle Trials
There are four Guardian Scout Is on the ledges. Use the shield bash to deflect their beams. Then shoot one of the Guardian Scout IIs with arrows to make it come to you.
Use Magnesis to get the chest from underwater. It contains an Eightfold Longblade.
Underground Floor 15: Middle Trials
This room contains a couple of Guardian Scout IIs. They will both attack at once. If they jump back and stick their weapons out, run behind a stone column so they will be stunned when they spin and hit it. There are some dry leaves on the floor if you want to float on an updraft to shoot them in slow motion.
From these enemies, you get a Guardian Sword+, Guardian Shield+, Guardian Spear, and Ancient Battle Axe. There are no treasure chests here, so just continue to the next room when you're ready.
Underground Floor 16: Middle Trials
This is the last room of the Middle Trials. This room contains a Guardian Scout IV. It drops a Guardian Spear+, Guardian Sword+, and Ancient Battle Axe+.
After you have completed the Beginning Trials, you can put the Master Sword into the pedestal again and select Final Trials to start the last set of trials.
Underground Floor 1: Final Trials
In this room, there is a thunderstorm, and you will be attacked by Stalkoblins. One of the Stalkoblins has a bow, so be sure to keep moving to avoid its arrows. You can find a Bokoblin Arm on the left side of the room, as well as some metallic weapons stuck in the ground. If you are having trouble, you can try to lure the Stalkoblins to the metallic weapons, which will sometimes get hit by lightning. Just don't stay too close to the weapons or you will get hit by the lightning as well.
Some of the weapons that can be found in this room are a few Bokoblin Arms, a Spiked Boko Club, Spiked Boko Spear, Spiked Boko Bat, Rusty Halberd, Rusty Broadsword, and Rusty Claymore. One of the Stalkoblins has a Spiked Boko Bow, and one of them has a Spiked Boko Shield. There is also a Rusty Shield in the room. Be sure to break the wooden crates to get more arrows.
Underground Floor 2: Final Trials
There is a thunderstorm in this room. There are also some Electric Keese in this room. They can be hit by lightning. They constantly shoot out sparks because of the storm, so you can't get close to them without getting shocked. Try to shoot them with arrows.
There is a skull in the middle of the room. When you go into the skull, three Stalizalfos will attack. They carry some metallic weapons that can be hit by lightning, so keep your distance if you see sparks.
You can acquire some meat in the dome, and some arrows, as well as another Spiked Boko Spear, and Lizal Forked Boomerang. The Stalizalfos may drop Lizalfos Arms. One of the Stalizalfos has a Reinforced Lizal Shield.
There is a buried metal treasure chest in one side of the room that you can pull up with Magnesis. It contains a Royal Guard's Sword. It is a strong weapon, but you will have to use it sparingly to avoid lightning strikes.
Underground Floor 3: Final Trials
There is a thunderstorm in this room. There are some spikes in the ground, so be sure to avoid walking into them and getting hurt. There are a couple of Electric Chuchus in this room. After you kill them and climb up onto the platform to reach the treasure chest, many Stalmoblins will come up from the ground. Shoot them in the head if you can.
Some of the weapons that you can acquire here are Moblin Arm, Spiked Moblin Spear, and Spiked Moblin Club, as well as a Dragon Bone Boko Bow. A treasure chest contains a Knight's Shield, a treasure chest that contains a Knight's Bow, and there are barrels that contain arrows.
Underground Floor 4: Final Trials
The thunderstorm continues in this room. There are many Stalkoblins on Stalhorses in this room. Try hiding behind one of the walls in this room and letting one Stalkoblin see you from a distance. Stay near the wall and shoot at the Stalkoblin as it comes near, then try to shoot its head to kill it. Repeat this until all of the Stalkoblins are dead. (You don't need to kill the Stalhorses.)
Be sure to open the crates in this room to get some fruit, mushrooms, arrows, and shock arrows.
Underground Floor 5: Final Trials
There is a thunderstorm in this room, and a Stalnox boss. The Stalnox is the only enemy in this room. Try shooting the Stalnox in the eye. If you succeed, the Stalnox will fall to the ground and you can hit it repeatedly. Eventually, the Stalnox's eye will fall out. Hit the eye until the Stalnox dies. It drops a Flamespear, a Great Frostblade, and a Thunderblade. There are crates in the room that contain arrows, and there is a buried metal treasure chest that you can pull up with Magnesis to get some ice arrows.
Underground Floor 6: Final Trials
This room contains no monsters. There are fairies in this room, so walk slowly. There is a cook fire. There are treasure chests that contain Flamebreaker Boots, a Knight's Bow, and three Ancient Arrows. The crates contain food and arrows. There are some Armored Carp in the pond.
Underground Floor 7: Final Trials
There is volcanic heat in this room, so be sure to equip the Flamebreaker Boots that you got in the previous room. There is a Fire Chuchu in this room, as well as a couple of Igneo Pebblits (you can kill them instantly with bombs) and a Rock Octorok (throw a bomb at it while it is inhaling, and it will swallow the bomb, which you can detonate to kill the Octorok). Float up on the updraft to reach the pillar if you want the Rusty Claymore that is embedded in it.
Underground Floor 8: Final Trials
There are three Fire-Breath Lizalfos in this room. They can shoot fire arrows at you. Use the updrafts to shoot at them in slow motion, but don't let your stamina run out. If you fall into the lava, you will lose a heart, but you won't have to start the Final Trials over. The crates contain some mushrooms and fire arrows.
Underground Floor 9: Final Trials
There is a Meteo Wizzrobe in this room. If you have ice arrows, you can kill it instantly by shooting it with one. Or if you still have the Great Frostblade from the Stalnox, you can kill it instantly with that. There are two Fire-Breath Lizalfos and a Black Moblin in the skull. The crates in the skull contain arrows and meat.
Underground Floor 10: Final Trials
There is a Fire-Breath Lizalfos on a nearby platform. Float to it after you kill the Lizalfos. There is a platform in the middle of the room with several Black Moblins on it. After you deal with them, be sure to break open the crates to get some food an arrows. There is also a metallic treasure chest in the lava near the base of the Moblin platform that contains some ancient arrows.
Underground Floor 11: Final Trials
There is an Igneo Talus in the center of this room. It won't attack until you approach it, so you might want to go around the edges of the room, bombing the piles of rocks to reveal some air vents, and breaking the metal crates to get a few arrows.
When you are fighting the Igneo Talus, you can float on the updrafts and then shoot the ore deposit on top of the Talus's head. If you have ice arrows or an ice weapon, you can hit the Talus with them to cool off its body, allowing you to climb up on top of it and hit the ore deposit with a melee weapon.
The Igneo Talus doesn't drop anything when defeated.
Underground Floor 12: Final Trials
This room contains no monsters. There are fairies in this room, so walk slowly. There is a cook fire. There are treasure chests that contain a Royal Guard's Shield, a Stone Smasher, and a Hylian Tunic. The crates contain food and arrows. There are some Sizzlefin Trout in the pond. Be sure to cook all of the spicy peppers and other cold resistance foods you might have.
Underground Floor 13: Final Trials
This room is very cold, so you will either need to equip a flame weapon to stay warm, or eat food that boosts cold resistance, if you have any. The cold resistance countdown will continue when you continue to the next floor if it has not run out by then.
There are a couple of Frost Pebblits and an Ice Chuchu that can all be killed with bombs. There are also three Black Bokoblins sitting around an unlit cook fire. After you kill these enemies, you can light the cook fire and cook some of the spicy peppers that you got in the previous room if you didn't cook them before.
Underground Floor 14: Final Trials
Kill the Ice Chuchus and the Ice-Breath Lizalfos on the ground. Then carefully go around the platform killing the Blue Bokoblins with arrows so they can't let the others know you are there.
Then you can use fire weapons to melt a chunk of ice to create an updraft. This will allow you to float up and shoot the remaining Blue Bokoblin in slow motion, leaving only the Silver Moblin.
The Silver Moblin will do a lot of damage with each attack, so try to kill it from a distance.
One of the ice chunks hides a treasure chest that contains three Ancient Arrows.
Underground Floor 15: Final Trials
Quickly use a fire arrow or other fire weapon on the Blizzrobe to kill it, then try to lure the Black Moblin to you without letting the Bokoblins see you. After that, you can try to sneak over to the Bokoblin camp and steal their weapons, or just shoot a bomb arrow between them to deal some damage before they can approach you. Hide behind the wall and they will go back to the campfire, allowing you to shoot them from a distance again.
Underground Floor 16: Final Trials
The only enemy here is a Frost Talus. It will not attack until you approach it, so go around the room melting the ice to create some updrafts. Then walk up to it to start the battle. You can hit it with flame weapons or a fire arrow to defrost it. It will fall forward when you do this, allowing you to climb on top and use the Stone Smasher on the ore deposit on its head. You can also just use the updrafts to shoot the ore deposit from the air. The Talus doesn't drop anything when defeated.
Underground Floor 17: Final Trials
The only enemy here is a Blue-Maned Lynel. You can instantly kill it with an Ancient Arrow. Or you can fight it the usual way if you prefer. Then melt the chunk of ice in this room to find a treasure chest that contains Bomb Arrows.
Underground Floor 18: Final Trials
This room contains no monsters. There are fairies in this room, so walk slowly. There is a cook fire. There are treasure chests that contain a Royal Bow, a Royal Shield, and a Royal Broadsword. The crates contain food and arrows. There are some Hearty Bass in the pond.
Underground Floor 19: Final Trials
The weather in the trials will be normal from now on. There are six Decayed Guardians in this room. Try to fight them one-by-one. You can instantly kill them with Ancient Arrows, but you might want to save those for later floors. There is a metallic treasure chest buried near one of the Guardians that contains a Knight's Shield.
Underground Floor 20: Final Trials
There is a Guardian in this room. There are also a couple of horses if you want to try to fight the Guardian from horseback. Ancient Arrows will deplete the Guardian's health quickly, but you will need to use more than one if you don't hit it directly in the eye. Try using Stasis to give yourself time to aim. Be sure to break the barrels and crates in this room to get some arrows.
Underground Floor 21: Final Trials
There is a Guardian Skywatcher in this room. It won't attack you unless it sees you. You can climb one of the towers and float from it to shoot the Skywatcher in slow motion. Shoot its propellers with bomb arrows to destroy them. Then the Skywatcher will fall to the ground, if it doesn't land upright, you can easily hit it with one of your strong melee weapons to finish it off. There are bomb arrows in a treasure chest on top of the tower in the middle. You can use Ancient Arrows to kill the Skywatcher more quickly, but it might take a few. Be sure to hit the barrel and crate in this room to get more arrows.
Underground Floor 22: Final Trials
This room has a Guardian, a Guardian Skywatcher, and a Guardian Turret. Run to the building in the middle, then go around to find the entrance, then hide inside. You can get a Royal Bow from the treasure chest in here, then go up the ladder to find a treasure chest that contains a Royal Shield. As with a previous room, there are some horses that you can ride if you want to try battling on horseback.
If you get behind the Turret and start hitting it, it won't be able to turn around for a while, so you can sneak up to the tower that it is on and climb around the back where the Turret can't aim. Then use your strongest melee weapons on the back of the Turret until it dies. If the Turret manages to turn around, just jump off of the tower and float down.
Be sure to look for the barrels and crates in the ruined houses and on the wall so you can get food and arrows.
Underground Floor 23: Final Trials
This is the final room. You are up against a White-Maned Lynel, a Guardian Turret, and eight Bokoblins on horseback. The Bokoblins will charge at you right away, but since they are low-level enemies, they can be killed quickly with the arrows that you gathered in the previous room. However, the Lynel will probably see you too and start running toward you. In addition, if you are standing in a bad spot, the Turret will start shooting at you as well. Quickly position yourself behind a large tree or other indestructible obstacle so the Turret can't shoot at you, then use Stasis on the Lynel and quickly kill it with an Ancient Arrow if you have one. Then try to quickly deal with the Bokoblins before they can swarm you. After the Bokoblins are all gone, then you can sneak up on the Guardian Turret like in the previous room and kill it. The treasure chest on the ruined building contains bomb arrows.