msem-instigator

At the beginning of each opponent's upkeep, that player may discard their hand. If the player does, sacrifice Under the Gun. Otherwise, put a bullet counter on Under the Gun, then that player loses life equal to the number of bullet counters on it.

{T}: Add {R} or {W}. You lose 1 life unless you have less life than an opponent.

Reach
{T}: Add one mana of any color. Spend this mana only to cast an Azra or Demon spell, and that spell can't be countered.

Dominance — When Mammoth Crab enters, draw a card if you control the creature with the greatest power or tied for the greatest power.

Flying, vigilance

Until end of turn, target creature you control gets +2/+0 and gains “When this creature dies, mill two cards, then return it to the battlefield under its owner's control.”

Choose one —
• Destroy target artifact.
• Destroy target enchantment.
• Destroy target creature with flying.

Disrupting Storms deals 3 damage to target player. That player sacrifices a land.

Equipped creature gets +2/+2 and has ward {2}.
Whenever a creature you control enters, if you cast it from exile, you may attach Minstrel's Armor to it.
Equip {2}

Pressure {1}{U}{U} (You may cast this spell for its pressure cost if seven or more cards are in your graveyard.)
Draw three cards.

Prowess
Whenever Balefire Conjurer attacks, you may pay {1}{R}. If you do, exile the top card of your library. You may play that card until the end of your next turn.

Wither (This deals damage to creatures in the form of -1/-1 counters.)

Legacy (You may play this side of this card only from your graveyard. Exile it if it would be put into a graveyard or not resolve.)
Volcano Sacrifice deals damage to target creature or planeswalker equal to the number of creature cards in your graveyard.

Creatures you control get +1/+1 until end of turn. Merfolk you control get an additional +1/+1 until end of turn.

Target creature gets +2/+2 and gains lifelink until end of turn. Whenever that creature perseveres this turn, target opponent loses 2 life. (A creature perseveres when it survives damage.)

You may pay {R} and tap an untapped Warrior you control rather than pay this spell's mana cost.
Choose one —
• Double the power of target creature you control until end of turn.
• Target creature you control deals damage equal to its power to target creature or planeswalker.

This spell costs {1} less for each Pirate and/or Rogue you control.
Counter target spell unless its controller pays {3}. If that spell is countered this way, exile it instead of putting it into its owner's graveyard.

Destroy target creature or planeswalker.
Crystallize. (Put a +1/+1 counter on a creature you control or create a Treasure.)

When Nomadic Patriarch enters, nourish 1. (To nourish 1, either put a +1/+1 counter on this creature or create a 1/1 white Citizen creature token.)
Remove a +1/+1 counter from Nomadic Patriarch: Put a +1/+1 counter on each other creature token you control.

Prowess
Whenever you cast an instant or sorcery spell, Tirenan Pyromancer deals 1 damage to each opponent.

When this creature enters, put a -1/-1 counter on a creature you control.
{2}{U}, {T}: For each permanent, you may give it a counter of a kind already there. Then draw a card for each permanent with three or more counters on it.

At the beginning of your end step, if a permanent you controlled left the battlefield this turn, put a party counter on Rambunctious Afterparty. Then Rambunctious Afterparty deals damage equal to the number of party counters on it to each opponent.

When Quillback dies, you may shuffle him into his owner's library. If you do, return up to one target Shaman creature card and up to one target non-Shaman creature card from your graveyard to your hand.

Whenever Fleshwarper or another Horror you control dies, each opponent loses 1 life and you gain 1 life. You may mill a card.

Untrekked Territory enters tapped.
{T}: Add {B} or {G}.
When Untrekked Territory enters, you may put a loyalty counter on a planeswalker you control.