Rat King, Depth 5
In Goo's main chamber, there is a secret door to the Rat King's room. It contains lots of chests most with low gold, but some armor and weapons.
Unlimited wand ammunition
This is an easy but time consuming cheat/glitch buy could be considered worth it. Due to the way a wands mechanics are made to work, you supposedly get one more "charge" to it, so for this and other reasons that I don't remember, if you drop your wand then pick it up again at least 40 times, it gets considered as a recharge on that move, so every action you take the wand will recharge.
NOTE: If you close down/exit the game, this glitch will reset
Challenges Mode...