Char-Rumbler

Double strike
{R}: Char-Rumbler gets +1/+0 until end of turn.

Inferno Titan

{R}: Inferno Titan gets +1/+0 until end of turn.
Whenever Inferno Titan enters or attacks, it deals 3 damage divided as you choose among one, two, or three targets.

Thran Dynamo

Ogre Menial

Infect (This creature deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)
{R}: Ogre Menial gets +1/+0 until end of turn.

Inferno of the Star Mounts

This spell can't be countered.
Flying, haste
{R}: Inferno of the Star Mounts gets +1/+0 until end of turn. When its power becomes 20 this way, it deals 20 damage to any target.

Dragon Hatchling

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

Spitfire Handler

Spitfire Handler can't block creatures with power greater than Spitfire Handler's power.
{R}: Spitfire Handler gets +1/+0 until end of turn.

Cavalier of Flame

{1}{R}: Creatures you control get +1/+0 and gain haste until end of turn.
When Cavalier of Flame enters, discard any number of cards, then draw that many cards.
When Cavalier of Flame dies, it deals X damage to each opponent and each planeswalker they control, where X is the number of land cards in your graveyard.

Everflame Eidolon

Bestow {2}{R} (If you cast this card for its bestow cost, it's an Aura spell with enchant creature. It becomes a creature again if it's not attached to a creature.)
{R}: Everflame Eidolon gets +1/+0 until end of turn. If it's an Aura, enchanted creature gets +1/+0 until end of turn instead.
Enchanted creature gets +1/+1.

Colos Yearling

Mountainwalk (This creature can't be blocked as long as defending player controls a Mountain.)
{R}: Colos Yearling gets +1/+0 until end of turn.

Fire-Belly Changeling

Changeling (This card is every creature type.)
{R}: Fire-Belly Changeling gets +1/+0 until end of turn. Activate no more than twice each turn.

Pygmy Pyrosaur

Pygmy Pyrosaur can't block.
{R}: Pygmy Pyrosaur gets +1/+0 until end of turn.

Kargan Dragonlord

Level up {R} ({R}: Put a level counter on this. Level up only as a sorcery.)
LEVEL 4-7
4/4
Flying
LEVEL 8+
8/8
Flying, trample
{R}: Kargan Dragonlord gets +1/+0 until end of turn.

Pyre Charger

Haste
{R}: Pyre Charger gets +1/+0 until end of turn.

Balduvian Hydra

Balduvian Hydra enters with X +1/+0 counters on it.
Remove a +1/+0 counter from Balduvian Hydra: Prevent the next 1 damage that would be dealt to Balduvian Hydra this turn.
{R}{R}{R}: Put a +1/+0 counter on Balduvian Hydra. Activate only during your upkeep.

Stonewright

Soulbond (You may pair this creature with another unpaired creature when either enters. They remain paired for as long as you control both of them.)
As long as Stonewright is paired with another creature, each of those creatures has "{R}: This creature gets +1/+0 until end of turn."

Sol Ring

Lightning Berserker

{R}: Lightning Berserker gets +1/+0 until end of turn.
Dash {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.)

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."

Nesting Dragon

Flying
Landfall — Whenever a land you control enters, create a 0/2 red Dragon Egg creature token with defender and "When this creature dies, create a 2/2 red Dragon creature token with flying and '{R}: This creature gets +1/+0 until end of turn.'"

Pia Nalaar

When Pia Nalaar enters, create a 1/1 colorless Thopter artifact creature token with flying.
{1}{R}: Target artifact creature gets +1/+0 until end of turn.
{1}, Sacrifice an artifact: Target creature can't block this turn.

Mountain

Moonveil Dragon

Flying
{R}: Each creature you control gets +1/+0 until end of turn.

Avatar of Fury

If an opponent controls seven or more lands, this spell costs {6} less to cast.
Flying
{R}: Avatar of Fury gets +1/+0 until end of turn.

Lathliss, Dragon Queen

Flying
Whenever another nontoken Dragon you control enters, create a 5/5 red Dragon creature token with flying.
{1}{R}: Dragons you control get +1/+0 until end of turn.

Homura's Essence

Creatures you control get +2/+2 and have flying and "{R}: This creature gets +1/+0 until end of turn."

Homura, Human Ascendant

Homura, Human Ascendant can't block.
When Homura dies, return it to the battlefield flipped.

Homura, Human Ascendant // Homura's Essence

Skyship Stalker

Flying
{R}: Skyship Stalker gets +1/+0 until end of turn.
{R}: Skyship Stalker gains first strike until end of turn.
{R}: Skyship Stalker gains haste until end of turn.

Fire Diamond

Fire Diamond enters tapped.
{T}: Add {R}.

Flamekin Brawler

{R}: Flamekin Brawler gets +1/+0 until end of turn.

Scourge of Valkas

Flying
Whenever Scourge of Valkas or another Dragon you control enters, it deals X damage to any target, where X is the number of Dragons you control.
{R}: Scourge of Valkas gets +1/+0 until end of turn.

Simian Spirit Guide

Exile Simian Spirit Guide from your hand: Add {R}.

Shivan Dragon

Flying
{R}: This creature gets +1/+0 until end of turn.

Goblin Fire Fiend

Haste
Goblin Fire Fiend must be blocked if able.
{R}: Goblin Fire Fiend gets +1/+0 until end of turn.

Akroma, Angel of Fury

This spell can't be countered.
Flying, trample, protection from white and from blue
{R}: Akroma, Angel of Fury gets +1/+0 until end of turn.
Morph {3}{R}{R}{R} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its morph cost.)