Enthusiastic Mechanaut

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

Jhoira, Weatherlight Captain

Whenever you cast a historic spell, draw a card. (Artifacts, legendaries, and Sagas are historic.)

Ashnod's Altar

Etherium Sculptor

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

Goblin Bombardment

Sacrifice a creature: Goblin Bombardment deals 1 damage to any target.

Phyrexian Altar

Sacrifice a creature: Add one mana of any color.

Boggart Shenanigans

Whenever another Goblin you control is put into a graveyard from the battlefield, you may have Boggart Shenanigans deal 1 damage to target player or planeswalker.

Ovika, Enigma Goliath

Flying
Ward—{3}, Pay 3 life.
Whenever you cast a noncreature spell, create X 1/1 red Phyrexian Goblin creature tokens, where X is the mana value of that spell. They gain haste until end of turn.

Impact Tremors

Whenever a creature you control enters, this enchantment deals 1 damage to each opponent.