Its a floating eye with bloody tentacles dangling below

His Creation
The evil lord of the nether a giant ghast Gastar had one eye. that eye gained a personality and tore itself out of Gastar and flew away. Ghastar now furious sends every living thing in the dimension to find his missing eye; Zombie pigmen, Magma Cubes, Blazes, and smaller ghasts. they searched for years but never found him, to this very day they are still searching.

His current life
After he ran away he didn't know what to do. he thought for several days before it came to him "I must have a purpose here otherwise why else would I be here." so he went in search of his purpose. One day he found a creature he never seen before, emerge from a square of hard black rock with swirly purple stuff in the middle, he looked like the zombie pigmen except his arms weren't raised and he didn't have pinky green skin. He thought about it and then an idea came to him. he slowly approached the strange being so as not to seem unfriendly, the creature didn't notice him he was to busy looking at a round object with a red stick spinning uncontrollably. he screams at the device and throws it away, he looks up to see a floating eyeball.the creature is now looking at me, what do I do, i don't know what to do, and so I started crying. the being seemed upset for me and gives me what appears to be a drop of water I blink it into my eye and, i feel so much better now that was very refreshing. The being (I think I'll call him steve) gestures me to go into the purple swirly stuff, I followed Steve through and what I see next I could never imagine. it's a green world filled with things I've never seen. All of a sudden a weird thing that looks like the zombie pigmen except it looked more like steve jumps out of the trees and attacks steve, now i'm mad I take my tentacles and grab the zombie and take him way up high then drop him to his death. steve congratulated me and gave me another drop of water. steve liked me doing that so every time I saw one I killed it. Then one day steve packed up some stuff and said that we are going to save the world from these horrid monsters. That is what he's doing to this day getting rid of all the monsters.