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.

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.

Fiery Islet

{T}, Pay 1 life: Add {U} or {R}.
{1}, {T}, Sacrifice Fiery Islet: Draw a card.

Skullcrack

Players can't gain life this turn. Damage can't be prevented this turn. Skullcrack deals 3 damage to target player or planeswalker.

Searing Blaze

Searing Blaze deals 1 damage to target player or planeswalker and 1 damage to target creature that player or that planeswalker's controller controls.
Landfall — If you had a land enter the battlefield under your control this turn, Searing Blaze deals 3 damage to that player or planeswalker and 3 damage to that creature instead.

Scalding Tarn

{T}, Pay 1 life, Sacrifice Scalding Tarn: Search your library for an Island or Mountain card, put it onto the battlefield, then shuffle.

Monastery Swiftspear

Haste
Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)

Boros Charm

Choose one —
• Boros Charm deals 4 damage to target player or planeswalker.
• Permanents you control gain indestructible until end of turn.
• Target creature gains double strike until end of turn.

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.

Lava Spike

Lava Spike deals 3 damage to target player or planeswalker.

Arid Mesa

{T}, Pay 1 life, Sacrifice Arid Mesa: Search your library for a Mountain or Plains card, put it onto the battlefield, then shuffle.

Mountain

Rift Bolt

Rift Bolt deals 3 damage to any target.
Suspend 1—{R} (Rather than cast this card from your hand, you may pay {R} and exile it with a time counter on it. At the beginning of your upkeep, remove a time counter. When the last is removed, you may cast it without paying its mana cost.)

Sacred Foundry

({T}: Add {R} or {W}.)
As Sacred Foundry enters, you may pay 2 life. If you don't, it enters tapped.

Lightning Bolt

Lightning Bolt deals 3 damage to any target.

Inspiring Vantage

Inspiring Vantage enters tapped unless you control two or fewer other lands.
{T}: Add {R} or {W}.

Sunbaked Canyon

{T}, Pay 1 life: Add {R} or {W}.
{1}, {T}, Sacrifice Sunbaked Canyon: Draw a card.