Mana Max, Afterburner 

Legendary Creature — Human Survivor Pilot
At the beginning of each player's end step, Mana Max deals damage to that player equal to the number of untapped lands they control. Whenever a player loses one or more unspent mana, each of that player's opponents creates a Treasure token.
Legality
standardNOT LEGALpioneerNOT LEGALmodernNOT LEGALlegacyNOT LEGALvintageNOT LEGALcommanderNOT LEGAL