Juaking

This spell can't be countered.
Haste, Trample, Vigilance, First Strike, Indestructible, Protection from coloured spells, Annihilator 10.
When this creature enters the battlefield, if it
wasn't cast from your hand by paying its full mana cost, sacrifice it.
At the beginning of your end phase, pay {10} or exile
it, if you do, take an extra turn.
If this card is exiled from the battlefield, you lose the
game.