Fireblast

You may sacrifice two Mountains rather than pay this spell's mana cost.
Fireblast deals 4 damage to any target.

Lightning Bolt

Lightning Bolt deals 3 damage to any target.

Eidolon of the Great Revel

Whenever a player casts a spell with mana value 3 or less, Eidolon of the Great Revel deals 2 damage to that player.

Goblin Guide

Haste
Whenever Goblin Guide attacks, defending player reveals the top card of their library. If it's a land card, that player puts it into their hand.

Skewer the Critics

Spectacle {R} (You may cast this spell for its spectacle cost rather than its mana cost if an opponent lost life this turn.)
Skewer the Critics deals 3 damage to any target.

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.