Carapace Forger

Metalcraft — Carapace Forger gets +2/+2 as long as you control three or more artifacts.

Darksteel Citadel

Tree of Tales

Maelstrom Colossus

Cascade (When you cast this spell, exile cards from the top of your library until you exile a nonland card that costs less. You may cast it without paying its mana cost. Put the exiled cards on the bottom in a random order.)

Gingerbrute

Haste
{1}: Gingerbrute can't be blocked this turn except by creatures with haste.
{2}, {T}, Sacrifice Gingerbrute: You gain 3 life.

Ornithopter

Ancient Stirrings

Look at the top five cards of your library. You may reveal a colorless card from among them and put it into your hand. Then put the rest on the bottom of your library in any order.

Metamorphosis

As an additional cost to cast this spell, sacrifice a creature.
Add X mana of any one color, where X is 1 plus the sacrificed creature's mana value. Spend this mana only to cast creature spells.

Phyrexian Walker

Winding Way

Choose creature or land. Reveal the top four cards of your library. Put all cards of the chosen type revealed this way into your hand and the rest into your graveyard.

Gingerbread Cabin

({T}: Add {G}.)
Gingerbread Cabin enters tapped unless you control three or more other Forests.
When Gingerbread Cabin enters untapped, create a Food token. (It's an artifact with "{2}, {T}, Sacrifice this artifact: You gain 3 life.")

Myr Enforcer

Affinity for artifacts (This spell costs {1} less to cast for each artifact you control.)

Rancor

Enchant creature
Enchanted creature gets +2/+0 and has trample.
When Rancor is put into a graveyard from the battlefield, return Rancor to its owner's hand.

Forest

Ulamog's Crusher

Annihilator 2 (Whenever this creature attacks, defending player sacrifices two permanents.)
Ulamog's Crusher attacks each combat if able.