The Infinity Egg is a block from the Witchery mod. It is a creative-only item, meaning it can only be accessed from the Creative inventory and the NEI cheat mode inventory. It is an upgrade for the Altar, giving it a +1000 power boost, a +10x power multiplier boost, and a +10x power recharge rate boost. It must be placed on the Altar.
It appears similar to a Dragon Egg, though it has red spots, and is less black. Like the Dragon Egg, clicking or right-clicking it will make it teleport to a different location. The same tricks can be used to pick it up, such as using a piston on it.