Gorynych, the Hellkite

Flying, Haste.
Gorynych, the Hellkite enter the battlefield with three head counters on it.
If damage would be dealt to Gorynych, the Hellkite, prevent that damage. Remove head counter from Gorynych, the Hellkite. If no head counter on Gorynych, the Hellkite sacrifice it.
Whenever Gorynych, the Hellkite attacks or blocks, you may pay {x} where X less or equal number of head counter on it. If you do Gorynych, the Hellkite get +X/+0 until end of turn.