Phantasmal Mount 

Creature — Illusion Horse
Flying
: Target creature you control with toughness 2 or less gets +1/+1 and gains flying until end of turn. When this creature leaves the battlefield this turn, sacrifice that creature. When the creature leaves the battlefield this turn, sacrifice this creature.
Legality
standardNOT LEGALpioneerNOT LEGALmodernNOT LEGALlegacyLEGALvintageLEGALcommanderLEGAL