Pyroblast

Choose one —
• Counter target spell if it's blue.
• Destroy target permanent if it's blue.

Seat of the Synod

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

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

Whenever a creature you control enters, Impact Tremors deals 1 damage to each opponent.

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

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

{1}, {T}, Sacrifice Chromatic Sphere: Add one mana of any color. Draw a card.

Lightning Bolt deals 3 damage to any target.

{1}, {T}, Sacrifice Chromatic Star: Add one mana of any color.
When Chromatic Star is put into a graveyard from the battlefield, draw a card.

As an additional cost to cast this spell, sacrifice an artifact.
Create three 1/1 red Goblin creature tokens.