Mana leech, introduced with Updates/10.94, is a way to receive mana from your opponent during fighting. It was initially available via Charging (which was removed with Updates/11.40) and later also by Imbuing certain equipment. When imbued, the item will receive a mana leech amount value (3%, 5% or 8%), which you will get as mana when you cause damage, if the item is equipped.