Kharasha Foothills is a common Plane — Mongseng card from Planechase 2012 Planes (OPC2), collector number 22. Current market price: $1.66, TCGplayer market prices via Scryfall.
Whenever a creature you control attacks a player, for each other opponent, you may create a token that's a copy of that creature, tapped and attacking that opponent. Exile those tokens at the beginning of the next end step. Whenever chaos ensues, you may sacrifice any number of creatures. If you do, Kharasha Foothills deals that much damage to target creature.