Toolcraft Exemplar

At the beginning of combat on your turn, if you control an artifact, Toolcraft Exemplar gets +2/+1 until end of turn. If you control three or more artifacts, it also gains first strike until end of turn.

Champion of the Flame

Trample
Champion of the Flame gets +2/+2 for each Aura and Equipment attached to it.

Loxodon Warhammer

Equipped creature gets +3/+0 and has trample and lifelink.
Equip {3}

Grafted Wargear

Equipped creature gets +3/+2.
Whenever Grafted Wargear becomes unattached from a permanent, sacrifice that permanent.
Equip {0} ({0}: Attach to target creature you control. Equip only as a sorcery.)

Valduk, Keeper of the Flame

At the beginning of combat on your turn, for each Aura and Equipment attached to Valduk, Keeper of the Flame, create a 3/1 red Elemental creature token with trample and haste. Exile those tokens at the beginning of the next end step.

Danitha Capashen, Paragon

First strike, vigilance, lifelink
Aura and Equipment spells you cast cost {1} less to cast.

Wind-Scarred Crag

This land enters tapped.
When this land enters, you gain 1 life.
{T}: Add {R} or {W}.

Darksteel Citadel

Vorrac Battlehorns

Equipped creature has trample and can't be blocked by more than one creature.
Equip {1} ({1}: Attach to target creature you control. Equip only as a sorcery. This card enters unattached and stays on the battlefield if the creature leaves.)

Teshar, Ancestor's Apostle

Flying
Whenever you cast a historic spell, return target creature card with mana value 3 or less from your graveyard to the battlefield. (Artifacts, legendaries, and Sagas are historic.)

Etched Champion

Metalcraft — Etched Champion has protection from each color as long as you control three or more artifacts.

Mountain

Kemba, Kha Regent

At the beginning of your upkeep, create a 2/2 white Cat creature token for each Equipment attached to Kemba, Kha Regent.

Great Furnace

Jor Kadeen, the Prevailer

First strike
Metalcraft — Creatures you control get +3/+0 as long as you control three or more artifacts.

Swiftblade Vindicator

Double strike (This creature deals both first-strike and regular combat damage.)
Vigilance (Attacking doesn't cause this creature to tap.)
Trample (This creature can deal excess combat damage to the player or planeswalker it's attacking.)

Wings of Hubris

Equipped creature has flying.
Sacrifice Wings of Hubris: Equipped creature can't be blocked this turn. Sacrifice it at the beginning of the next end step.
Equip {1} ({1}: Attach to target creature you control. Equip only as a sorcery.)

Plains

Mask of Memory

Whenever equipped creature deals combat damage to a player, you may draw two cards. If you do, discard a card.
Equip {1} ({1}: Attach to target creature you control. Equip only as a sorcery.)

Stone Haven Outfitter

Equipped creatures you control get +1/+1.
Whenever an equipped creature you control dies, draw a card.

Shambling Suit

Shambling Suit's power is equal to the number of artifacts and/or enchantments you control.

Ardent Recruit

Metalcraft — Ardent Recruit gets +2/+2 as long as you control three or more artifacts.

Indomitable Archangel

Flying
Metalcraft — Artifacts you control have shroud as long as you control three or more artifacts. (An artifact with shroud can't be the target of spells or abilities.)