The Fiery End

As an additional cost to cast this spell, sacrifice a mountain.
The Fiery End deals {x}+1 damage to any {x} different targets. If any creature or planeswalker
would be put in the graveyard this way, exile
them instead. If you used only red mana to pay
for {x}, destroy target {x} lands divided by half
(round down each time), if you didn't, The Fiery
End deals {x} damage to you.
It all started with smoke. It will finish in ashes...