Dream Spoilers

Flying

Whenever you cast a spell during an opponent's turn, you may have target creature get -1/-1 until end of turn.

Flying, lifelink

Whenever you cast a spell during an opponent's turn, put a -1/-1 counter on up to one target creature.

Whenever a creature you control explores, target creature an opponent controls gets -2/-2 until end of turn.

Whenever another creature you control enters, target creature an opponent controls gets -1/-1 until end of turn.

Flying

Modular 3 (This creature enters with three +1/+1 counters on it. When it dies, you may put its +1/+1 counters on target artifact creature.)

Whenever another artifact you control enters, target creature an opponent controls gets -1/-1 until end of turn.

Whenever you cast an enchantment spell, you may have target creature get -2/-2 until end of turn.