Mirrodin Besieged

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

At the beginning of your upkeep, you may put a charge counter on target artifact.

{2}{U}, {T}: Put a -1/-1 counter on target creature. You may tap or untap that creature.

When Treasure Mage enters the battlefield, you may search your library for an artifact card with converted mana cost 6 or greater, reveal it, put i...

Shroud (This creature can't be the target of spells or abilities.) Whenever Neurok Commando deals combat damage to a player, you may draw a card.

Equipped creature gets +1/+0 and has first strike. Equip {1}

Living weapon (When this Equipment enters the battlefield, create a 0/0 black Germ creature token, then attach this to it.) Equipped creature gets ...

Sphere of the Suns enters the battlefield tapped and with three charge counters on it. {T}, Remove a charge counter from Sphere of the Suns: Add on...

Living weapon (When this Equipment enters the battlefield, create a 0/0 black Germ creature token, then attach this to it.) Equipped creature gets ...

When Piston Sledge enters the battlefield, attach it to target creature you control. Equipped creature gets +3/+1. Equip—Sacrifice an artifact.

When Pierce Strider enters the battlefield, target opponent loses 3 life.

Infect (This creature deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.) Phyrexian Juggernaut ...

When Peace Strider enters the battlefield, you gain 3 life.

Living weapon (When this Equipment enters the battlefield, create a 0/0 black Germ creature token, then attach this to it.) Equipped creature gets ...

Flying

When Leonin Relic-Warder enters the battlefield, you may exile target artifact or enchantment. When Leonin Relic-Warder leaves the battlefield, ret...

Battle cry (Whenever this creature attacks, each other attacking creature gets +1/+0 until end of turn.)

{T}: Attach target Equipment you control to target creature you control.

Metalcraft — Spiraling Duelist has double strike as long as you control three or more artifacts.

Infect (This creature deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.) When Viridian Corrupt...

Vigilance Kemba's Legion can block an additional creature each combat for each Equipment attached to Kemba's Legion.

{T}, Sacrifice a creature: Proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Melira's Keepers can't have counters put on it.