msem-instigator

Protection from Dawn Chord (This creature can't be blocked, targeted, dealt damage, or enchanted by anything named Dawn Chord.)
{1}{R}: Target Reflection's base power becomes equal to Dusk Chord's power until end of turn.

Menace, haste

Whenever you cast a spell with mana value 5 or greater, create an X/1 red Mutant creature token with trample and haste, where X is that spell's mana value. Exile that token at the beginning of the next end step.

Flying
Grandstanding Huma can block only creatures with flying.
{2}{R}{R}, Exile three instant and/or sorcery cards from your graveyard: Return Grandstanding Huma from your graveyard to the battlefield tapped and attacking. Activate this ability only during your declare attackers step.

Whenever a creature in Heaven's Fire Ascetic's pack attacks, that creature deals 1 damage to defending player. (Two or more creatures you control with equal power are in a pack.)

Flying, haste
Whenever you attack with three or more creatures, harmonize three times. (To harmonize, trigger up to one harmony of a permanent you control.)
If you would harmonize, you may instead return Herald of Festivities from your graveyard to your hand.

When Ikari-no-Oni enters, other creatures you control get +1/+0 until end of turn.

When Jaakuna Bloodsworn enters, any opponent may have it deal 3 damage to them. If a player does, sacrifice Jaakuna Bloodsworn.

This spell costs {1} less to cast for each embattled creature you control. (A creature is embattled if it has a counter on it or a permanent you control attached to it.)
Haste
Whenever Knights of the Burning Pyre attacks, it deals X damage to each opponent, where X is the number of embattled creatures you control.

(Transcend as a sorcery to gain that type and a +1/+1 counter.)
When Kui Mu Lang enters, exile a card from your graveyard. When you do, Kui Mu Lang deals damage equal to that card's mana value to up to one target creature or planeswalker.
{2}{R}: Demigod — Exile your hand, then draw three cards.
{4}{R}{R}: God — Cast any number of cards exiled with Kui Mu Lang without paying their mana costs.

Whenever a player looks at one or more cards in your library or searches your library, Lavamind Elemental deals 2 damage to that player. (This includes you.)
At the beginning of your end step, look at the bottom card of your library. You may put it on top of your library.

If a red instant or sorcery spell you control or a red planeswalker you control would deal damage to a permanent or player, it deals that much damage plus 2 instead.

When Miasma Spewer enters, you may sacrifice a permanent. When you do, Miasma Spewer deals 1 damage to each opponent and each creature and planeswalker they control.

Trample, haste
When Oil Driller enters, salvage two cards at random. (Exile those cards from your graveyard until this creature leaves the battlefield. Whenever this creature deals combat damage to a player, put a card it salvaged into your hand.)
At the beginning of your end step, sacrifice Oil Driller.

Whenever Ore Tunneler deals damage to an opponent, tap target land they control. It doesn't untap during its controller's next untap step.

Out-of-Depth Amateur can't attack or block alone.
Attain {4}{R} ({4}{R}: Transform this. Spend at least three colors of mana to activate this, and only as a sorcery.)

Outfitted Ibex has menace as long as it's embattled. (A creature is embattled if it has a counter on it or a permanent you control attached to it.)

Outlands Bodyguard can't attack alone.
You may exert Outlands Bodyguard as it attacks. When you do, it must be blocked this turn if able. (An exerted creature won't untap during your next untap step.)

Flying

Flying, haste
{2}{R}{R}, Exile a multicolored card from your graveyard: Return Rainbow Phoenix from your graveyard to the battlefield tapped. If it's your declare attackers step, it enters attacking.

When Ravenous Abomination enters, choose one —
• Create two Treasure tokens.
• Put a +1/+1 counter on Ravenous Abomination.

Reach
Whenever you cast a spell with mana value 5 or greater, Reaper Squad deals 3 damage to target player or planeswalker.

Trample, haste
When Red Pelt Hart deals combat damage to a player, return it to its owner's hand.
At the beginning of your end step, sacrifice Red Pelt Hart.

Menace
When Santriza Gang-Boss enters, it deals X damage to any target, where X is the number of Pirates and/or Rogues you control.