Rottenmouth Viper — Bloomburrow Promos #107p

As an additional cost to cast this spell, you may sacrifice any number of nonland permanents. This spell costs less to cast for each permanent sacrificed this way.

Whenever this creature enters or attacks, put a blight counter on it. Then for each blight counter on it, each opponent loses 4 life unless that player sacrifices a nonland permanent of their choice or discards a card.