msem-instigator

Hexproof
At the beginning of each end step, if an opponent was dealt 4 or more damage this turn, return target instant or sorcery card from your graveyard to your hand.

Deception {1}{B}
When Aguri, Shadow of Doubt enters, target player reveals their hand. You choose a nonland card from it. That player discards that card. You lose 2 life.

{T}: Scry 1.
{1}{U}, {T}: Draw a card.

Search your library for a card and put that card into your hand. Then shuffle.
When Tharyen's Machinations is engorged, you may search your library for a card with the same mana value as the permanent that engorged it, reveal it, put it into your hand, then shuffle.

Advance {3}{R} (Cast this for {3}{R} to advance it as it enters. {3}{R}: Advance this as a sorcery.)
Whenever another artifact creature you control enters or a permanent you control advances, Skalorian Orbguard deals 1 damage to any target.

Creatures you control get +0/+2 until end of turn. Untap those creatures.

First strike (This creature deals combat damage before creatures without first strike.)
Whenever you cast an instant or sorcery spell, Flamemaster Insurgent gets +X/+0 until end of turn, where X is that spell's mana value.

Deathtouch
Whenever another creature named Winter's Whelp you control enters, you draw a card and you lose 1 life.

Flying
Other Vampire creatures you control get +1/+0 and have menace.

Whenever a creature an opponent controls deals damage to you, monstrosity 2. (If this creature isn't monstrous, put two +1/+1 counters on it and it becomes monstrous.)
Frigid Behemoth can't attack unless it's monstrous.

(Transform this if it's not attached to a creature. Pay {1}{W} as a sorcery to unattach it.)
Enchant creature you control
Mount of Heroes's rider gets +2/+1.
Sacrifice Mount of Heroes: Counter target spell that targets you or Mount of Heroes's rider.

Slipstream (This creature can't be blocked as long as only creatures with slipstream are attacking.)
Concord — As long as there are four or more card types among permanents you control, Bubbledome Waveblade gets +1/+1.

When Elvish Skyranger enters, search your library for a card with a basic land type, put it onto the battlefield tapped, then shuffle.

When Undying Lich dies, create a 6/3 black Zombie Horror creature token with menace and “When this creature dies, create an 8/5 black Elder Demon Horror creature token with flying, deathtouch, and menace.”

Search your library for up to two Forest cards, reveal those cards, put one onto the battlefield tapped and the other into your hand, then shuffle.
Flashback—Tap three untapped green creatures you control. (You may cast this card from your graveyard for its flashback cost. Then exile it.)

You may play an additional land this turn.
Return target permanent card from your graveyard to your hand. Exile Whispers of the Dark.

Puzzlebox (Begin the game with this and another card you own from outside the game in the command zone, locked. That card is face down until you unlock this.)
{2}, Discard your hand: Unlock Traitor's Gambit. If the revealed card is red, put it into your hand. Otherwise, put it on top of your library.

When Dawson's Warden enters, create a Treasure token.
As long as you control three or more artifacts, Dawson's Warden gets +2/+0 and has first strike.

[+1]: Choose up to one target creature. Until your next turn, whenever that creature attacks you or Kimar, Kimar deals 4 damage to that creature.
[–1]: Put a +1/+1 counter on target creature. That creature gains lifelink until end of turn.
[–7]: Search your library for a creature card and put it onto the battlefield. You gain life equal to its power. Then shuffle.

Target creature gets -3/-3 until end of turn. Scry 2.

Enchant creature
When Strike Fear enters, draw a card.
When enchanted creature attacks, target creature can't block this turn.

Hibernation Den enters tapped.
{T}: Add {W}.
{W}, {T}: You gain 1 life. Activate only as a sorcery and only if you control a white creature.

Golden age (If you cast an instant or sorcery spell, activated a nonmana ability, and attacked this turn, enter a renaissance for this game.)
{1}, Sacrifice a creature: Draw a card. Each opponent loses 1 life and you gain 1 life.
Whenever you sacrifice a creature, if you're in a renaissance, each opponent sacrifices a creature. This ability triggers only once each turn.

Other Warriors you control have first strike.
Other Barbarians you control get +1/+0.

When Salty Swab enters, exile the top three cards of your library.
Resolute — You may play cards exiled with Salty Swab as long as Salty Swab's power is greater than its base power.