Mirrodin Besieged

Put a -1/-1 counter on target creature. When that creature dies this turn, its controller gets a poison counter.

Choose one — • Counter target artifact spell. • Return target artifact to its owner's hand.

Counter target spell, then proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Create X 2/2 white Cat creature tokens. Shuffle White Sun's Zenith into its owner's library.

Attacking creatures get +1/+0 and gain first strike until end of turn.

Destroy target creature with flying. Its controller gets a poison counter.

Return up to two target nonland permanents to their owners' hands.

Target creature gets +1/+1 and gains trample until end of turn.

Destroy target creature with flying. Its controller gets a poison counter.

Target creature gets +2/+2 until end of turn. Metalcraft — That creature gets +4/+4 until end of turn instead if you control three or more artifacts.

Attacking creatures get +1/+0 and gain first strike until end of turn.

Exile two target artifacts.

Destroy target noncreature artifact.

Put any number of target artifact cards from your graveyard on top of your library. Draw a card.

Burn the Impure deals 3 damage to target creature. If that creature has infect, Burn the Impure deals 3 damage to that creature's controller.

Destroy target artifact. You gain life equal to its converted mana cost.

Put a -1/-1 counter on each attacking creature.

Creatures your opponents control get -2/-0 until end of turn.

Return up to two target nonland permanents to their owners' hands.

Put target artifact, creature, or enchantment on top of its owner's library.

Create two 1/1 colorless Myr artifact creature tokens.

Target player draws X cards. Shuffle Blue Sun's Zenith into its owner's library.

Target creature gets +1/+1 and gains trample until end of turn.

Target creature gets +2/+2 until end of turn. Metalcraft — That creature gets +4/+4 until end of turn instead if you control three or more artifacts.