msem-instigator

Flash
Ocean's Edge Kraken enters with a hexproof counter on it.
{6}{U}{U}, Remove a hexproof counter from Ocean's Edge Kraken: Return all other creatures to their owners' hands.

Whenever a creature you control dies, you may pay {G}. If you do, draw a card.

Flying, haste
Miyoga Flameweaver can't block.
Whenever Miyoga Flameweaver attacks, exile the top card of your library. You may play that card until end of turn.

Whenever a land you control enters, create a 1/1 red Elemental creature token. Then if you control three or more Elementals, exile Aleryn, Trapseeker, then return him to the battlefield transformed under his owner's control.

Menace
When Rallios Unleashed enters, create a 2/2 black Zombie creature token.
Whenever Rallios Unleashed deals combat damage to a player, create a 2/2 black Zombie creature token for each creature card in your graveyard.

Draw a card, then copy target activated or triggered ability you don't control. You may choose new targets for the copy.
Exile Confirm Hypothesis.

Exile target creature with power 3 or less. You gain 3 life.

Whenever an embattled creature you control dies, you may return Skhorvall Eternal from your graveyard to your hand. (A creature is embattled if it has a counter on it or has a permanent you control attached to it.)

Enchant land
When Contested Discovery enters and at the beginning of your upkeep, untap enchanted land. You gain control of that land until end of turn.

Rhapsody {5}{R}{W} (Pay {5}{R}{W} to cast this as a 4/4, or as a sorcery to make it become a 4/4.)
Whenever a creature you control with power 4 or greater attacks, look at the top four cards of your library. You may cast a nonland card with mana value 3 or less from among them without paying its mana cost. Put the rest on the bottom of your library in a random order.

This spell costs {1} less to cast for each permanent sacrificed this turn.
Destroy target noncreature permanent.

First strike (This creature deals combat damage before creatures without first strike.)

First strike

({T}: Add {W}.)
Sacred Sanctuary enters tapped with two sanctum counters on it.
{T}, Remove a sanctum counter from Sacred Sanctuary: Add {G} or {U}.

At the beginning of your upkeep, create a 1/1 green Saproling creature token.
Whenever a creature you control dies, put a +1/+1 counter on Heart of Spores.
{X}{G}: Move X +1/+1 counters from Heart of Spores onto target creature. Activate only as a sorcery.

Converge — Precursor Sentinel enters with a +1/+1 counter on it for each color of mana spent to cast it.
Remove a +1/+1 counter from Precursor Sentinel: It deals 1 damage to any target.

Enchant creature
When Lost to the Elements enters, if enchanted creature isn't in a pack, tap it. (Two or more creatures with the same controller and equal power are in a pack.)
Enchanted creature doesn't untap during its controller's untap step.

Target creature gets +2/+0 and gains first strike until end of turn. If it's a Dragon, put a +1/+1 counter on it.

Menace
When Icilica's Icestrider enters, choose one —
• Draw a card if you own a card in exile.
• Target player discards a card if that player owns a card in exile.

Foretell {1}{B} (During your turn, you may pay {2} and exile this card from your hand face down. Cast it on a later turn for its foretell cost.)
Return up to two target creature cards from your graveyard to your hand.

[+1]: Return target nonland permanent to its owner's hand. That player loses 2 life.
[0]: Create a 1/1 blue Bird creature token with flying for each loyalty counter on The Flock.
[–6]: You get an emblem with “If a permanent you don't control would leave the battlefield, you may instead exile it, then return that card to the battlefield under your control. It's a 1/1 blue Bird creature with flying.”

Flash
Voracious 2 (As this enters, you may sacrifice up to two artifacts and/or creatures. This creature enters with that many +1/+1 counters on it.)

Flying
When Ephara's Watcher enters, scry 2.

When Campaign Recruiter enters, you may search your library for a creature card with first strike, double strike, flying, improve, lifelink, melee, or vigilance, reveal it, put it into your hand, then shuffle.

{T}: Add {C}.
{3}, {T}, Sacrifice Hall of Random Access Memories: Return target artifact, instant, or sorcery card from your graveyard to your hand.