A treacherous belt that generates Mana by feeding on its wearer.
Epic Equipment card.
The Girdle is one of a few ways to break the mana economy of the game. Its greatest utility lies in those moments when you are only a few mana away from an upgrade needed for the next wave. It also allows you the flexibility to use spells without hampering your upgrade plans.
Note that you will not accrue mana with this item when waves are called early, and so must balance your strategy when calling early to advance spell cooldowns. Once upgraded to level 2+, you will always gain more mana by waiting.
If both you and a friend's borrowed Avatar have Girdles equipped, the mana generation stacks.