Ice Mutant Ship

Flying, trample, indestructible
(Damage and effects that say "destroy" don't destroy
this creature. If its toughness is 0 or less, it's still put
into its owner's graveyard.)
Crew X (Tap any number of creatures you control
with total power X or more: This Vehicle becomes
an artifact creature with power X until end of turn.)
"The original Death Triangle"