Core Prowler

Infect (This creature deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)
When Core Prowler dies, proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Darksteel Sentinel

Flash (You may cast this spell any time you could cast an instant.)
Vigilance
Indestructible (Damage and effects that say "destroy" don't destroy this creature. If its toughness is 0 or less, it's still put into its owner's graveyard.)

Ugin's Nexus

If a player would begin an extra turn, that player skips that turn instead.
If Ugin's Nexus would be put into a graveyard from the battlefield, instead exile it and take an extra turn after this one.

Etherium Sculptor

Artifact spells you cast cost {1} less to cast.

It That Heralds the End

Colorless spells you cast with mana value 7 or greater cost {1} less to cast.
Other colorless creatures you control get +1/+1.

Vedalken Archmage

Whenever you cast an artifact spell, draw a card.

Hedron Matrix

Equipped creature gets +X/+X, where X is its mana value.
Equip {4}

Renari, Merchant of Marvels

You may cast Dragon spells and artifact spells as though they had flash.
Choose a Background (You can have a Background as a second commander.)

Jin-Gitaxias, Progress Tyrant

Whenever you cast an artifact, instant, or sorcery spell, copy that spell. You may choose new targets for the copy. This ability triggers only once each turn. (A copy of a permanent spell becomes a token.)
Whenever an opponent casts an artifact, instant, or sorcery spell, counter that spell. This ability triggers only once each turn.

Archetype of Imagination

Creatures you control have flying.
Creatures your opponents control lose flying and can't have or gain flying.

Creepy Doll

Indestructible
Whenever Creepy Doll deals combat damage to a creature, flip a coin. If you win the flip, destroy that creature.

Invisible Stalker

Hexproof (This creature can't be the target of spells or abilities your opponents control.)
Invisible Stalker can't be blocked.

Nettlecyst

Living weapon (When this Equipment enters, create a 0/0 black Phyrexian Germ creature token, then attach this to it.)
Equipped creature gets +1/+1 for each artifact and/or enchantment you control.
Equip {2}

Soul of New Phyrexia

Trample
{5}: Permanents you control gain indestructible until end of turn.
{5}, Exile Soul of New Phyrexia from your graveyard: Permanents you control gain indestructible until end of turn.

Workshop Assistant

When Workshop Assistant dies, return another target artifact card from your graveyard to your hand.

Shield of the Avatar

If a source would deal damage to equipped creature, prevent X of that damage, where X is the number of creatures you control.
Equip {2} ({2}: Attach to target creature you control. Equip only as a sorcery.)

Tomb of the Spirit Dragon

{T}: Add {C}.
{2}, {T}: You gain 1 life for each colorless creature you control.