Sigil of Sleep

Enchant creature
Whenever enchanted creature deals damage to a player, return target creature that player controls to its owner's hand.

Brainstorm

Draw three cards, then put two cards from your hand on top of your library in any order.

Reckless Fireweaver

Whenever an artifact you control enters, Reckless Fireweaver deals 1 damage to each opponent.

Lightning Bolt

Lightning Bolt deals 3 damage to any target.

Ponder

Look at the top three cards of your library, then put them back in any order. You may shuffle.
Draw a card.

Banishing Knack

Until end of turn, target creature gains "{T}: Return target nonland permanent to its owner's hand."

Island

Mountain

Ashnod's Altar

Mirran Spy

Flying
Whenever you cast an artifact spell, you may untap target creature.

Counterspell

Ornithopter

Golem Foundry

Whenever you cast an artifact spell, you may put a charge counter on Golem Foundry.
Remove three charge counters from Golem Foundry: Create a 3/3 colorless Golem artifact creature token.

Myr Retriever

When Myr Retriever dies, return another target artifact card from your graveyard to your hand.

Galvanic Blast

Galvanic Blast deals 2 damage to any target.
Metalcraft — Galvanic Blast deals 4 damage instead if you control three or more artifacts.

First Day of Class

Whenever a creature you control enters this turn, put a +1/+1 counter on it and it gains haste until end of turn.
Learn. (You may reveal a Lesson card you own from outside the game and put it into your hand, or discard a card to draw a card.)