Go to Dellston, Find Rita, Ask her about 'coffee' Then say 'perfect'
Hold down the SHIFT key, Press the keys 7,8,9,0
A special message will appear
On the first level, go down to the bottom-left of the map. (You can't cast Magic Map, but you can use Orbs of Sight.)
Get into the very bottom-left room. You will need to use the dispel barrier spell or Crystals of piercing. The route is very obvious.
Put a pair of Pants (the inventory item) on the pillar, then step on the rune :) Add