Mightstone

Destroy target land.

Reach (This creature can block creatures with flying.)

Creatures you control get +1/+1 as long as you control no nonartifact, nonwhite creatures.

T: Prevent the next 2 damage that would be dealt to target artifact creature this turn.

Destroy all lands.

Flying

Each player chooses a number of lands they control equal to the number of lands controlled by the player who controls the fewest, then sacrifices the rest. Players discard cards and sacrifice creatures the same way.