The Great Stygian Abyss, the dungeon opposite Humility.

On level 1 at the Altar, use a stone at the shrine and then pick Honesty and the Blue stone.

On level 5 in the rooms, you need to step on the square where the Zorn starts to open the wall. (Kill the Zorn to remove the Negate magic so you can dispell the field.) Go past into the infamous reaper room. The reapers can't put you to sleep if you're poisoned. Step on the two south-east most squares in the room to open the walls. East is an easier room than south.

At the Altar, pick Sacrifice and the Orange stone.

On level 6 there are a bunch of rooms which look sort of like this:

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These rooms are tricky. The correct order to travel these rooms is 143674580A. In room #5, step on the square occupied by the northeast most balron to open the south wall. In room #8, step on the square occupied by the east balron to create a new square next to the south balron. Step on the new square to create a bridge.

When you get to the Altar, pick Honor and the Purple stone.

On level 7, there are a series of rooms you must pass. In the room with the undead and gazers, step on the secret wall to the southeast to gain access to the monsters. Then step in the nook near the center of the room to open the walls. In the room with the balron, daemons, and skeletons, step on the secret walls to gain access to the monsters.

At the Altar, pick Spirituality and the White stone.