Mirrodin

{W}, {T}: Tap target artifact.

{T}: Add {B}.

{T}: Add {R}.

Nim Devourer gets +1/+0 for each artifact you control. {B}{B}: Return Nim Devourer from your graveyard to the battlefield, then sacrifice a creatur...

Flying Whenever an artifact enters the battlefield under your control, you may tap target permanent.

At the beginning of your upkeep, put a +1/+1 counter on Myr Prototype. Myr Prototype can't attack or block unless you pay {1} for each +1/+1 counte...

When Leveler enters the battlefield, exile all cards from your library.

{T}: Add {W}.

Whenever Dross Scorpion or another artifact creature dies, you may untap target artifact.

{T}: Add {G}.

Trample Clockwork Vorrac enters the battlefield with four +1/+1 counters on it. Whenever Clockwork Vorrac attacks or blocks, remove a +1/+1 counter...

Whenever Flayed Nim deals combat damage to a creature, that creature's controller loses that much life. {2}{B}: Regenerate Flayed Nim.

Trample Whenever Living Hive deals combat damage to a player, create that many 1/1 green Insect creature tokens.

Sacrifice an artifact: Krark-Clan Grunt gets +1/+0 and gains first strike until end of turn.

First strike, haste

As long as Leonin Den-Guard is equipped, it gets +1/+1 and has vigilance.

Sacrifice an artifact: Atog gets +2/+2 until end of turn.

Fear (This creature can't be blocked except by artifact creatures and/or black creatures.) Whenever Woebearer deals combat damage to a player, you ...

Defender (This creature can't attack.) Pay 1 life: Wall of Blood gets +1/+1 until end of turn.

Whenever an artifact enters the battlefield, Vermiculos gets +4/+4 until end of turn.

Whenever Slith Bloodletter deals combat damage to a player, put a +1/+1 counter on it. {1}{B}: Regenerate Slith Bloodletter.

Flying Nim Shrieker gets +1/+0 for each artifact you control.

Nim Shambler gets +1/+0 for each artifact you control. Sacrifice a creature: Regenerate Nim Shambler.