After you do battle with Azala and the BlackTyrano, you travel to a different era.
Leave the Cave
Exit the cave and go east. Go into the skyway and walk north to be transported. Go south to go outside.
Go east to the building and enter Enhasa.
Go to the northeast area and check on the book on the table.
Then go up the northwest stairs to meet a strange kid. After that, continue up the stairs and check the book on the table.
Before moving on, step on that blue circle below you to heal HP and MP.
Finally, go to the middle of the south part of the big room, near where you entered, and open the book there. Go through the door that appears.
Check on the Nu to fight six Nus.
These Nus have two attacks: take your HP down to 1, or damage you by 1. This means that if your HP is 1 and they hit you with the "damage by 1" attack, you will die. So whenever your HP is 1, heal up. Crono and Ayla's Falcon Hit can be used to attack three of the Nus at once. It should only take two Falcon Hits to kill a row.
You will get a Magic Tab and a Speed Tab if you win. You can optionally read the book on the table. When you are done, exit the room.
Enhasa, Part 2
Before leaving Enhasa, use the blue circle in the northwest again to heal up. Then go outside, and go north to the Land Bridge. Step on the platform to be sent down below, then go south to go outside. Go north and use the Skyway there to go back up above. Go west across the bridge and check on the building to the west, the one that is called Kajar. Enter Kajar.
Go northwest and open the book there. Then go southeast and open the book there. Finally, go to the middle of the area and open the book near the sleeping Nu. Go through the door that opens, and check the Poyozo Doll to get a Black Rock. This is an accessory, but it can only be equipped by certain characters, and can't be used for its full potential yet, so just hold onto it for now. You can optionally read the book on the table. Then exit the room.
Go through the northeast door. Now head through the door at the top right. In here, check the bottom right wall to find a Speed Tab.
Before you go, you might want to talk to the sleeping Nu to buy supplies.
Now leave Kajar and go back outside.
Go east and enter the cave. Step into the light, then go outside. Go east to the next cave, step into the light, then go outside. Go east, then north, and enter Zeal palace.
Go to the west side of the area, then go north and up the first set of stairs. Talk to the woman who is standing next to a little sapling. Tell her that you like plants, and tell her to secretly plant the sapling. Otherwise, you will miss out on something later.
Then go north, then east, and talk to the Nu who is walking around. Agree to scratch its back. Now, if you go back to Kajar, go through the northeast door, talk to the Nu looking at the bookshelf, and you'll scratch its back, and get a Magic Tab.
Back in Zeal Palace, go into the northeast door, then go through the door on the right. Watch the cutscene. Follow Schala out, then go south, then go through the middle door in the north of the main hall. Go north and watch Schala.
Go south to return to the main hall, then go northwest and talk to the Nu, and it will move out of the way. Go north through the door, then go north to the next room.
NOTE: Once you check on the red sparkle, you won't be able to leave the palace.
If you need supplies, go back to Kajar and talk to the sleeping Nu to buy what you need.
If you are ready, check on the red sparkle in the hall of the Mammon Machine in Zeal Palace.
Before moving on, replace Ayla with Lucca, and make everyone in your active party wear Ruby Vests.
Go back through the middle door in the northern part of Zeal Palace, and go north to the door that Schala opened with her pendant. Walk up to it to open it. Go through.
Go north. After the cutscene, there will be a battle.
You can lose this battle if you don't feel like fighting, but you will miss out on a good amount of experience points.
Throughout the battle, keep your HP above 120. Golem has a fireball attack that is likely to kill the party member that it hits, so be prepared to use Revives as needed. Start the battle with Crono's Lightning2, then use Lucca's Fire. If you cast an elemental spell on Golem, he will counter with that element, but not right away. Since you have Ruby Vests, it is recommended to have Lucca attack with Fire. Since Golem is slow to counter, you can use Lightning2 on him and then follow right away with Fire, and Golem won't hit with lightning. If you hit Golem with a physical attack, he counters with Iron Orb, which halves your HP.
Zeal Palace, Part 2
Whether you win or lose, the same thing happens. Watch the cutscene and you will be back in the past.