Disallow

Counter target spell, activated ability, or triggered ability. (Mana abilities can't be targeted.)

Roon of the Hidden Realm

Vigilance, trample
{2}, {T}: Exile another target creature. Return that card to the battlefield under its owner's control at the beginning of the next end step.

Tale's End

Counter target activated ability, triggered ability, or legendary spell.

Sundial of the Infinite

{1}, {T}: End the turn. Activate only during your turn. (Exile all spells and abilities from the stack. Discard down to your maximum hand size. Damage wears off, and "this turn" and "until end of turn" effects end.)

Containment Priest

Flash
If a nontoken creature would enter and it wasn't cast, exile it instead.

Discontinuity

During your turn, this spell costs {2}{U}{U} less to cast.
End the turn. (Exile all spells and abilities from the stack, including this card. The player whose turn it is discards down to their maximum hand size. Damage wears off, and "this turn" and "until end of turn" effects end.)

Replicate

Create a token that's a copy of target creature you control.

Repudiate

Counter target activated or triggered ability. (Mana abilities can't be targeted.)