He hates Homeworlders and is out to shatter them all.
He also hates crystal gems because of his evil intentions to shatter all gems, except for Blue Zircon.
He has intentions to kill humans as well, or enslave them, so he can rule the universe.
Blue Zircon is his sister. He brought her back from the dead and plans to shatter Yellow Diamond and the other Homeworlders.
Painite can shatter gems, but he can't do it very well.
He can also create clones of himself, creating the Painite Force, each clone has 1/4th of the power Painite does.
He also can grow red wings to fly.
Finally, Painite can revive shattered gems, That is what he did to Blue Zircon.