msem-instigator

Enchant creature
Enchanted creature has “Whenever this creature attacks, if there are at least two other attacking creatures, this creature gains +2/+2 until end of turn.”

Return up to two target instant and/or sorcery cards from your graveyard to your hand, then you may cast an instant or sorcery card with mana value 2 or less from your hand without paying its mana cost. Exile Alchemical Warfare.

When Confine to the Oasis enters, exile target nonland permanent an opponent controls until Confine to the Oasis leaves the battlefield.
Whenever an opponent casts a spell, put a searching counter on Confine to the Oasis for each of that card's colors. Then if there are ten or more searching counters on Confine to the Oasis, sacrifice it and you gain 3 life.

Witchseeker Mob's power and toughness are each equal to twice the number of Citizens and/or Peasants you control.
When Witchseeker Mob enters, exile target nonland permanent an opponent controls with mana value less than or equal to Witchseeker Mob's power until Witchseeker Mob leaves the battlefield.

Choose X. You may choose the same mode more than once.
• Each opponent discards a card.
• Return target creature card from your graveyard to your hand.
• Each opponent loses 1 life and you gain 1 life.

At the beginning of your end step, if you gained life this turn, you gain 2 life.
Pay 3 life: Target attacking creature gains indestructible until end of turn.

{3}{U}, Reveal this card from your hand, Return an unblocked attacking creature you control to its owner's hand: Put Phasewalker Rake from your hand onto the battlefield tapped and attacking. If you returned a Pirate or Rogue this way, draw a card.

Flash
When Qililia's Scavenger enters, look at the top six cards of your library. You may put a Merfolk card with lesser mana value from among them onto the battlefield. Put the rest on the bottom of your library in a random order.
Other Merfolk you control get +1/+1.

Choose target creature with the greatest power or tied for the greatest power, then destroy all other creatures.

Menace
Savage Stalker attacks each combat if able.

Advance {6}{W}{W} (Cast this for {6}{W}{W} to advance it as it enters. {6}{W}{W}: Advance this as a sorcery.)
Flying, vigilance, lifelink
Whenever Valera, Constructed Angel advances, destroy all nonartifact creatures.

Each player returns each instant and sorcery card from their graveyard to their hand. Exile Ebb and Flow.

Whenever you draw your second card each turn, draw a card.

When Possibility Engine enters, exile the top two cards of your library.
Wanderlust — During each of your turns, if you control four or more differently named lands, you may play a card exiled with Possibility Engine.

As Ocean Monastery enters, you may pay 2 life. If you don't, Ocean Monastery enters tapped.
{T}, Sacrifice Ocean Monastery: Search your library for a Plains or Island card, put it onto the battlefield, then shuffle.

Equipped creature gets +1/+0, has no name, and loses all non-Pirate, non-Rogue creature types.
{1}: Equipped creature gains the creature types and activated abilities of target creature and its name becomes that creature's name until end of turn.
Equip {1}

Target creature gets +3/+0 and gains first strike until end of turn.

Cosmic Catastrophe deals 6 damage to target creature or planeswalker. If you control a creature with power greater than its base power, Cosmic Catastrophe deals 3 damage to each opponent.

Primal {3}{U}{U} (During your turn, you may cast this spell for {3}{U}{U} instead of playing a land.)
Draw a card for each land you control, then discard that many cards unless this spell was cast for its primal cost.

Exile target artifact, enchantment, or tapped creature.

Whenever you gain life for the first time each turn, create a 1/1 white Cleric creature token.

First strike
When Engulfing Incubus enters, you may submerge target nontoken creature an opponent controls. When Engulfing Incubus is no longer on the battlefield, turn that card face up. (To submerge a card, exile it, then put it on the battlefield face down under its owner's control as a 2/2 creature.)

Counter target spell with mana value 3 or less. If a spell is countered this way, return it to its owner's hand instead of putting it anywhere else.

Attacking creatures you control get +1/+0.

[+1]: Create a 1/1 green Scout creature token. If you control six or more lands, also create a 1/1 white Bird creature token with flying.
[–1]: Reveal the top card of your library. If it's a land card, put it onto the battlefield. Otherwise, put it into your hand.
[–5]: You get an emblem with “Whenever each permanent you control becomes tapped for the first time each turn, untap it.”