Powered Spawner

The Powered Spawner is a machine from Ender IO that spawns creatures when supplied power. It will spawn mobs as far as 4 blocks away.

After crafting the machine, it must be combined with a broken spawner on an anvil to set the type of mob it will spawn. Broken spawners can be acquired by breaking a vanilla Minecraft spawner. Initially a broken spawners type will be whatever it was when it was broken. But a broken spawners type can be changed by combining it with a Soul Vial of the desired type in a Soul Binder. This allows you to build a spawner for creatures you normally wouldn't be able to. The Powered Spawner is upgradeable with capacitors for increased power usage and spawn rate.

More Info
Powered Spawner on the Ender IO Wiki