Dionus, Elvish Archdruid 
Legendary Creature — Elf Druid
Elves you control have "Whenever this creature becomes tapped during your turn, untap it and put a +1/+1 counter on it. This ability triggers only once each turn."
Legality
standardNOT LEGALpioneerNOT LEGALmodernNOT LEGALlegacyLEGALvintageLEGALcommanderLEGAL