I can think of only 1 case where no food or water is needed for a char, if that is the point of OP, and I am doing this with my lock. Affliction spec, get Demon Armor on, DS a voidwalker and spam Siphon Filter and Drain Life. Get mana with Life Tap. 
I can think of only 1 case where no food or water is needed for a char, if that is the point of OP, and I am doing this with my lock. Affliction spec, get Demon Armor on, DS a voidwalker and spam Siphon Filter and Drain Life. Get mana with Life Tap.