Alibou, Ancient Witness

Other artifact creatures you control have haste.
Whenever one or more artifact creatures you control attack, Alibou, Ancient Witness deals X damage to any target and you scry X, where X is the number of tapped artifacts you control.

Fellwar Stone

{T}: Add one mana of any color that a land an opponent controls could produce.

Marble Diamond

Marble Diamond enters tapped.
{T}: Add {W}.

Hedron Archive

{T}: Add {C}{C}.
{2}, {T}, Sacrifice this artifact: Draw two cards.

Mountain

Sol Ring

Thought Vessel

You have no maximum hand size.
{T}: Add {C}.

Talisman of Conviction

{T}: Add {C}.
{T}: Add {R} or {W}. Talisman of Conviction deals 1 damage to you.

Liquimetal Torque

{T}: Add {C}.
{T}: Target nonland permanent becomes an artifact in addition to its other types until end of turn.

Boros Locket

{T}: Add {R} or {W}.
{R/W}{R/W}{R/W}{R/W}, {T}, Sacrifice Boros Locket: Draw two cards.

Worn Powerstone

Worn Powerstone enters tapped.
{T}: Add {C}{C}.

Cultivator's Caravan

{T}: Add one mana of any color.
Crew 3 (Tap any number of creatures you control with total power 3 or more: This Vehicle becomes an artifact creature until end of turn.)

Arcane Signet

{T}: Add one mana of any color in your commander's color identity.

Cursed Mirror

{T}: Add {R}.
As Cursed Mirror enters, you may have it become a copy of any creature on the battlefield until end of turn, except it has haste.

Thran Dynamo

Plains

Fire Diamond

Fire Diamond enters tapped.
{T}: Add {R}.

Boros Signet

Commander's Sphere

{T}: Add one mana of any color in your commander's color identity.
Sacrifice Commander's Sphere: Draw a card.

Basalt Monolith

Basalt Monolith doesn't untap during your untap step.
{T}: Add {C}{C}{C}.
{3}: Untap Basalt Monolith.