msem-instigator

Defender
Whenever another creature you control enters, Orphan of the Nav gets +1/+1 until end of turn and can attack as though it didn't have defender this turn.

Whenever you cast an enchantment spell, you may pay {W}. If you do, put a +1/+1 counter on target creature.

While searching your library, you may play basic land cards from your library.
You may play an additional land each turn.

Enchant creature
Enchanted creature gets -1/-3.

Stampede — Whenever Cloud's Roar Avenger and a creature with greater power attack, tap up to one target creature.

{W}, {T}: Remove target creature you control from combat.

Enchant creature
Enchanted creature has winnow. (Damage dealt to it also causes its controller to lose that much life.)

At the beginning of your upkeep, return target enchantment card from your graveyard to your hand.
Whenever Reflect on Serenity or another enchantment you control enters or leaves the battlefield, each opponent loses 1 life and you gain 1 life.

Flash
Flying
{2}{B}, Exile three cards from your graveyard: Create a tapped 2/2 black Zombie creature token.

Primal {U} (During your turn, you may cast this spell for {U} instead of playing a land.)
Counter target spell.

Target opponent exiles a card from their hand. Scry 2.
Tether (Then if you cast this from your hand, you may exile it tethered to a creature you control. When it dies, you may cast this from exile without paying its mana cost.)

Exile target creature you control, then return it to the battlefield under its owner's control.
Flashback {2}{W} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

This spell costs {1} less to cast for each permanent you control that's an artifact and/or a token.
When Kellythross's Collector enters, you may return another target nonland permanent to its owner's hand.

Vigilance
When this creature enters, create a 1/1 blue Bird creature token with flying.

Glitch {2} (Remove one [restriction] for each time you pay the glitch cost.)
Improbable Aim deals damage to target creature or planeswalker equal to the number of [instant and sorcery] cards in your graveyard.

If Wandering Domovoi would be dealt noncombat damage, prevent that damage and put three +1/+1 counters on Wandering Domovoi instead.

As an additional cost to cast this spell, sacrifice a creature.
Kindle the Cursed deals 3 damage to target creature and 3 damage to that creature's controller.

Menace, lifelink
When Fallen Hero leaves your graveyard, if it wasn't exiled, you may return target creature card not named Fallen Hero from your graveyard to your hand.

Whenever you cast an instant or sorcery spell, put a loyalty counter on Xenocrata and tap up to one target permanent.
[0]: Each opponent can't untap more than three permanents during their next untap step.
[–3]: Xenocrata deals 6 damage divided as you choose among any number of target creatures and/or planeswalkers.
[–9]: Cast any number of instant and/or sorcery cards you own in exile and from your graveyard without paying their mana costs.

Rhapsody {5}{R}{R} (Pay {5}{R}{R} to cast this as a 4/4, or as a sorcery to make it become a 4/4.)
When Corrupted Guardian enters, it deals damage equal to its power to up to one target player or planeswalker.

You draw two cards, lose 2 life, then mill two cards.

{2/W}, {T}: Tap target creature.

As an additional cost to cast this spell, sacrifice a creature.
Put X +1/+1 counters on target creature you control, where X is the sacrificed creature's power. You gain X life.

({T}: Add {B} or {G}.)
As Eerie Bayou enters, you may pay {1}. If you don't, Eerie Bayou enters tapped.

Enchant player
Whenever enchanted player casts a spell, they reveal cards from the top of their library until they reveal a card that shares a type with that spell, then puts all cards revealed this way into their graveyard.