Barreling Attack 
Instant
Target creature gains trample until end of turn. When that creature becomes blocked this turn, it gets +1/+1 until end of turn for each creature blocking it.
Legality
standardNOT LEGALpioneerNOT LEGALmodernNOT LEGALlegacyLEGALvintageLEGALcommanderLEGAL