msem-instigator

Menace
Whenever Skhorvall Warleader attacks, it gets +1/+0 until end of turn for each other attacking Warrior you control.

When Fish Out of Water enters, exile the top four cards of each library.
During each of your turns, you may cast a card exiled with Fish Out of Water without paying its mana cost.

({T}: Add {U} or {B}.)
As Ruptured Grotto enters, you may pay {1}. If you don't, Ruptured Grotto enters tapped.

Counter target spell. For each other card named Overcharge in your graveyard, create a colorless Canister artifact token with “{T}, Sacrifice this artifact: Add {C}.”

When Form of the Sunbird enters, it deals 4 damage to each creature. Your life total becomes 4.
If you would lose the game, instead transform Form of the Sunbird.

Exile target creature you control, then return that card to the battlefield under your control. Scry 1.

This spell costs {1} less to cast for each card you've drawn this turn.
Copy target instant or sorcery spell. You may reselect modes and choose new targets for the copy.

Flying
Dragonwrought Engineer gets +1/+1 for each artifact and enchantment you control.

Whenever you cast a noncreature spell, Architect of Calamity deals 2 damage to each opponent.

At the beginning of combat on your turn, if you cast an enchantment spell, an instant spell, and a sorcery spell this turn, create two 3/3 red Shark enchantment creature tokens. You may have any number of those tokens gain haste. If you do, sacrifice the tokens you chose at end of combat.

Draw three cards. (Then exile this card. You may cast the creature later from exile.)

Return target Actor or enchantment card from your graveyard to the battlefield.

Defender
Territorial Fangwurm may attack as though it didn't have defender as long as you've cast a cryptic spell this turn. (Artifacts, enchantments, and modal spells are cryptic.)

Target creature gets +2/+2 until end of turn. Draw a card if that creature has a counter on it.

Put all attacking creatures on top of their owners' libraries.

({T}: Add {G}, {W}, or {U}.)
Stalwart Dominion enters tapped.

Prowess

When Godseeker Vanguard enters, create two 1/1 green Scout creature tokens.

When Forserval enters, creatures you control get +1/+1 and gain haste until end of turn.

Prevent all damage that would be dealt to creatures and to you this turn.

Defender, reach
Aetherlock Effigy can block an additional creature each combat.
When Aetherlock Effigy dies, create two 1/1 black Bird creature tokens with flying.

(Add a quest counter as this enters. Sacrifice after 3.)
Once each turn, when you cast an instant or sorcery spell, you may add a quest counter.
1, 2 — Slipsand Expedition deals damage equal to the number of quest counters on it to any target.
3 — Add {R}{R}{R}.

Flash
When Hidden Sprout enters, put a +1/+1 counter on target creature.

Mentor (Whenever this creature attacks, put a +1/+1 counter on target attacking creature with lesser power.)
Masked Lancer has first strike as long as it's attacking.
Whenever Masked Lancer mentors a creature, that creature gains first strike until end of turn.

Whenever a nonbasic land becomes tapped or enters tapped, it doesn't untap during its controller's untap steps for as long as Ataraxia remains on the battlefield.