Sai, Master Thopterist

Whenever you cast an artifact spell, create a 1/1 colorless Thopter artifact creature token with flying.
{1}{U}, Sacrifice two artifacts: Draw a card.

Island

Foundry Inspector

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

Kappa Cannoneer

Improvise (Your artifacts can help cast this spell. Each artifact you tap after you're done activating mana abilities pays for {1}.)
Ward {4}
Whenever this creature or another artifact you control enters, put a +1/+1 counter on this creature and it can't be blocked this turn.

Etherium Sculptor

Voyager Quickwelder

Voyage Home

Affinity for artifacts (This spell costs {1} less to cast for each artifact you control.)
You draw three cards and gain 3 life.

Mendicant Core, Guidelight

Mendicant Core's power is equal to the number of artifacts you control.
Start your engines! (If you have no speed, it starts at 1. It increases once on each of your turns when an opponent loses life. Max speed is 4.)
Max speed — Whenever you cast an artifact spell, you may pay {1}. If you do, copy it. (The copy becomes a token.)

Plains

Thought Monitor

Affinity for artifacts (This spell costs {1} less to cast for each artifact you control.)
Flying
When this creature enters, draw two cards.