After escaping the Seaside Palace and defeating the Vampires in Mu, you go through the underwater tunnel to reach Angel Village.
Explore the Village
If you go down the ladder in the village where your other friends went, you can talk to them. Otherwise, go back outside and go west to another ladder. Go down. Go east to find some stairs leading down to the lower level, then go west along a narrow ledge. Go into the door along this ledge to reach the Dance Hall. Check on the fountain north of the door to find Red Jewel #24.
Leave the Dance Hall and go west, then go into the next door. Go west from here and go into the room to find a Dark Space. Then leave that room and go east, behind the waterfall. Go east past the waterfall and check on the door to open it. This leads to the dungeon.
Path to Ishtar
Go east, killing the monsters along the way. Go into the first door that you find. From there, go west, killing monsters, and go into the door at the end. Go east in the next room and kill the monsters, then go into the door at the end.
This next room has many doors. Before proceeding, go all the way to the east, killing all of the monsters you encounter. Then go to the west end of the room and go into the second door from the left. Kill the Steel Bones in the room, then go into the easternmost door. This is a dead end, but you can kill all of the enemies in this room to ensure that you get all of the powerups in the dungeon. Go back up the stairs to return to the room with five doors. Go all the way to the east side and go into the door there. Kill the enemies in that room and go back upstairs.
Now go left and into the second door from the right. Follow the path, killing monsters on the way. In the dark room, stay near the floor to avoid the dive bats. Keep going until you reach what seems to be a dead end in a room with flowing water, plants, and statues. Check on the wall between the two torches that point away from each other. You will find a hidden door. Go in.
Kill all the enemies in here. Slide into the crack next to the door to find Red Jewel #25. Then slide back out of the room and go into the door to the east.
This is the Wind Tunnel. You have to double tap in the direction that you want to go in order to run quickly enough to make any progress. There are two monsters in this room. You have to dash into them, but be careful to stay out of the way of their fireballs. Your HP increases when they are gone. Keep going east until you reach the exit. Go in.
Kill the many monsters in the next room to increase your DEF. Then slide into the crack in the east side of the room. In the next area, check on the middle of the north wall to find the hidden passage. Go inside. Go east past the waterfalls. The first door has a picture of Kara, who is trapped in the painting. Go into the second door and check the red jar on the left to get Red Jewel #26. Then go into the third door. You find Ishtar, who tells you to solve his riddles to rescue Kara. Go into the door.
Go into the door directly north of you. Ishtar asks you to memorize the room. When you are done, leave the room, then go east and into the door there. Ishtar asks what is different in this room from the previous room. Move the arrow onto the jar on the right side of the room. (In the previous room, this jar was red.)
Leave the room and go east to the second pair of doors. Go into the first door that you find. Memorize this room. Then go into the room to the east. Put the arrow on the two jars, which were red in the previous room.
Leave the room and go east to the third pair of doors. Go into the room and open the treasure chest, which contains an herb. If you don't get it now, you'll never be able to get it again. Leave the room, then go east to the next room. Put the cursor on the treasure chest. Open it to get Red Jewel #27.
Leave the room and go east to the fourth pair of doors. Then leave the room and go east to the next door. Put the cursor on Will, whose hair is blowing in the wind unlike in the previous room where there was no wind.
Leave the room and run to the west end, then use the door in the south wall. Talk to Ishtar, who is now trapped in the painting. Open the chest to get Magic Dust. Go south from Ishtar's room, then go west and into the third door from the right. Use the Magic Dust on Kara's painting. Neil says to talk to him when you are ready to go to the Floating City. Feel free to go back into the Angel Village to use the Dark Space there and save the game. Then go back and talk to Neil, and you will all go to the Floating City of Watermia.