Unstable Mutation

Enchant creature
Enchanted creature gets +3/+3.
At the beginning of the upkeep of enchanted creature's controller, put a -1/-1 counter on that creature.

Goblin Artisans

{T}: Flip a coin. If you win the flip, draw a card. If you lose the flip, counter target artifact spell you control that isn't the target of an ability from another creature named Goblin Artisans.

Lightning Bolt

Lightning Bolt deals 3 damage to any target.

Strip Mine

{T}: Add {C}.
{T}, Sacrifice this land: Destroy target land.

Shatterstorm

Destroy all artifacts. They can't be regenerated.

Taiga

Volcanic Island

Black Lotus

{T}, Sacrifice this artifact: Add three mana of any one color.

Power Leak

Enchant enchantment
At the beginning of the upkeep of enchanted enchantment's controller, that player may pay any amount of mana. This Aura deals 2 damage to that player. Prevent X of that damage, where X is the amount of mana that player paid this way.

Time Walk

Mountain

Red Elemental Blast

Choose one —
• Counter target blue spell.
• Destroy target blue permanent.

Timetwister

Each player shuffles their hand and graveyard into their library, then draws seven cards. (Then put Timetwister into its owner's graveyard.)

Goblin King

Other Goblins get +1/+1 and have mountainwalk.

Merfolk of the Pearl Trident

Howling Mine

At the beginning of each player's draw step, if this artifact is untapped, that player draws an additional card.

Sword of the Ages

This artifact enters tapped.
{T}, Sacrifice this artifact and any number of creatures you control: This artifact deals X damage to any target, where X is the total power of the creatures sacrificed this way, then exile this artifact and those creature cards.

Lord of Atlantis

Other Merfolk get +1/+1 and have islandwalk. (They can't be blocked as long as defending player controls an Island.)

Island

Chain Lightning

Chain Lightning deals 3 damage to any target. Then that player or that permanent's controller may pay {R}{R}. If the player does, they may copy this spell and may choose a new target for that copy.

Shatter

Mons's Goblin Raiders

Ancestral Recall

Psionic Blast

Psionic Blast deals 4 damage to any target and 2 damage to you.

Mox Ruby

Goblin Balloon Brigade

{R}: This creature gains flying until end of turn.

Wheel of Fortune

Each player discards their hand, then draws seven cards.

Blue Elemental Blast

Choose one —
• Counter target red spell.
• Destroy target red permanent.