Furious Clasher

Whenever Furious Clasher attacks, it gets +X/+0 until end of turn. X is the number of creatures the defending player controls. If X is five or more, Furious Clasher gains trample until end of turn. If X is seven or more, Furious Clasher gains deathtouch until end of turn. If X is ten or more, Furious Clasher gains double strike until end of turn.