Scepter of Empires

{T}: Scepter of Empires deals 1 damage to target player or planeswalker. It deals 3 damage instead if you control artifacts named Crown of Empires and Throne of Empires.

Opaline Unicorn

Island

Thirst for Knowledge

Draw three cards. Then discard two cards unless you discard an artifact card.

Chariot of Victory

Equipped creature has first strike, trample, and haste.
Equip {1}

Sword of Vengeance

Equipped creature gets +2/+0 and has first strike, vigilance, trample, and haste.
Equip {3}

Narnam Cobra

{G}: Narnam Cobra gains deathtouch until end of turn. (Any amount of damage it deals to a creature is enough to destroy it.)

Barbed Battlegear

Barricade Breaker

Improvise (Your artifacts can help cast this spell. Each artifact you tap after you're done activating mana abilities pays for {1}.)
Barricade Breaker attacks each combat if able.

Forest

Kitesail

Equipped creature gets +1/+0 and has flying.
Equip {2} ({2}: Attach to target creature you control. Equip only as a sorcery.)

Throne of Empires

{1}, {T}: Create a 1/1 white Soldier creature token. Create five of those tokens instead if you control artifacts named Crown of Empires and Scepter of Empires.

Crown of Empires

{3}, {T}: Tap target creature. Gain control of that creature instead if you control artifacts named Scepter of Empires and Throne of Empires.

Welding Sparks

Welding Sparks deals X damage to target creature, where X is 3 plus the number of artifacts you control.

Hovermyr

Loxodon Warhammer

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

Myr Enforcer

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

Shrapnel Blast

As an additional cost to cast this spell, sacrifice an artifact.
Shrapnel Blast deals 5 damage to any target.

Skyscanner

Flying
When Skyscanner enters, draw a card.

Mountain

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.)