Rakdos Locket

{T}: Add {B} or {R}.
{B/R}{B/R}{B/R}{B/R}, {T}, Sacrifice Rakdos Locket: Draw two cards.

Boltwing Marauder

Flying
Whenever another creature you control enters, target creature gets +2/+0 until end of turn.

Forgestoker Dragon

Flying
{1}{R}: Forgestoker Dragon deals 1 damage to target creature. That creature can't block this combat. Activate only if Forgestoker Dragon is attacking.

Mountain

Rakdos Pit Dragon

{R}{R}: Rakdos Pit Dragon gains flying until end of turn.
{R}: Rakdos Pit Dragon gets +1/+0 until end of turn.
Hellbent — Rakdos Pit Dragon has double strike as long as you have no cards in hand.

Kolaghan Monument

{T}: Add {B} or {R}.
{4}{B}{R}: Kolaghan Monument becomes a 4/4 black and red Dragon artifact creature with flying until end of turn.

Sparktongue Dragon

Flying
When Sparktongue Dragon enters, you may pay {2}{R}. When you do, it deals 3 damage to any target.

Rakdos Guildgate

This land enters tapped.
{T}: Add {B} or {R}.

Bloodfell Caves

This land enters tapped.
When this land enters, you gain 1 life.
{T}: Add {B} or {R}.

Dragon Egg

Defender
When Dragon Egg dies, create a 2/2 red Dragon creature token with flying and "{R}: This creature gets +1/+0 until end of turn."

Severed Strands

As an additional cost to cast this spell, sacrifice a creature.
You gain life equal to the sacrificed creature's toughness. Destroy target creature an opponent controls.

Foul-Tongue Invocation

As an additional cost to cast this spell, you may reveal a Dragon card from your hand.
Target player sacrifices a creature of their choice. If you revealed a Dragon card or controlled a Dragon as you cast this spell, you gain 4 life.

Reckless Rage

Reckless Rage deals 4 damage to target creature you don't control and 2 damage to target creature you control.

Swamp

Dragon Hatchling

Flying
{R}: Dragon Hatchling gets +1/+0 until end of turn.

Furnace Whelp

Flying
{R}: Furnace Whelp gets +1/+0 until end of turn.

Last Gasp

Target creature gets -3/-3 until end of turn.

Draconic Roar

As an additional cost to cast this spell, you may reveal a Dragon card from your hand.
Draconic Roar deals 3 damage to target creature. If you revealed a Dragon card or controlled a Dragon as you cast this spell, Draconic Roar deals 3 damage to that creature's controller.

Kolaghan, the Storm's Fury

Flying
Whenever a Dragon you control attacks, creatures you control get +1/+0 until end of turn.
Dash {3}{B}{R} (You may cast this spell for its dash cost. If you do, it gains haste, and it's returned from the battlefield to its owner's hand at the beginning of the next end step.)