Corrupted Goku was an alternate path for Goku to take on his path on a Super Saiyan. There were 3 sides. 1) The God Saiyan. 2)The Evil Saiyan. And the rare path, the corrupted saiyan. The corrupted saiyan is only achieved by killing his loved ones while maintaining no regret or pity. Once that is done, he will become into a corrupted saiyan. The only corrupted saiyan in the alternate realm is Corrupted Goku.

He is goku but with evil powers
Has 2 sides
normal Goku
and Goku evil
still pure heart