(An ongoing scheme remains face up until it's abandoned.)At the beginning of combat on your turn, up to one target creature gets +2/+2 and gains vigilance until end of turn. It can't be blocked this turn.At the beginning of each opponent's end step, if that player has less than half their starting life total, abandon this scheme.
Whenever an opponent activates an ability of an artifact, creature, or land on the battlefield, if it isn't a mana ability, Harsh Mentor deals 2 damage to that player.
Whenever Tectonic Giant attacks or becomes the target of a spell an opponent controls, choose one —• Tectonic Giant deals 3 damage to each opponent.• Exile the top two cards of your library. Choose one of them. Until the end of your next turn, you may play that card.
When They Came from the Pipes enters, manifest dread twice. (To manifest dread, look at the top two cards of your library. Put one onto the battlefield face down as a 2/2 creature and the other into your graveyard. Turn it face up any time for its mana cost if it's a creature card.)Whenever a face-down creature you control enters, draw a card.
MenaceWhen Massacre Girl enters, each other creature gets -1/-1 until end of turn. Whenever a creature dies this turn, each creature other than Massacre Girl gets -1/-1 until end of turn.
When you set this scheme in motion, put five +1/+1 counters on a creature you control and it gains flying and vigilance until end of turn. If you control no creatures, instead create a 4/4 colorless Scarecrow artifact creature token with vigilance.
(An ongoing scheme remains face up until it's abandoned.)Whenever you attack, create a 5/5 black Demon creature token with flying that's tapped and attacking.At the beginning of each end step, if two or more creatures died under your control this turn, abandon this scheme.
Exile target creature. Its controller manifests the top card of their library. (That player puts the top card of their library onto the battlefield face down as a 2/2 creature. If it's a creature card, it can be turned face up any time for its mana cost.)
TrampleAt the beginning of combat on your turn, mill a card and choose an opponent at random. Ursine Monstrosity attacks that player this combat if able. Until end of turn, Ursine Monstrosity gains indestructible and gets +1/+1 for each card type among cards in your graveyard.