msem-instigator

Draw a card, then draw cards equal to the number of cards named Sea Cache in your graveyard.

{3}{U}, {T}: Copy target instant or sorcery spell you control. You may choose new targets for the copy.

Archive 13 (As this enters, shuffle the top thirteen cards of your main library into a new face up library. Sacrifice this after the archived library is empty.)
At the beginning of your upkeep, you lose half your life, rounded up, and you draw half of the cards from the archived library, rounded up.

Flying
Heretic (Whenever you cast a spell that doesn't share a color with this creature, it gets +1/+1 until end of turn.)

When Digital Divinity enters, put a +1/+1 counter on each creature you control.
Whenever you gain life, you may return Digital Divinity to its owner's hand.

Stampede — Whenever Etlan High Priest and a creature with greater power attack, Etlan High Priest gets +1/+1 until end of turn. Then you gain 1 life and scry 1.

If an effect would create one or more tokens under your control, it creates twice that many of those tokens instead.
If an effect would put one or more counters on a permanent you control, it puts twice that many of those counters on that permanent instead.

Concord — Silt-Trench Brute gets +3/+3 and has trample as long as there are four or more card types among permanents you control.

You may exchange a creature you both own and control with a creature card in your hand that has the same mana value.
Flashback {1}{G} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Living weapon (When this Equipment enters, create a 0/0 black Phyrexian Germ creature token, then attach this to it.)
Equipped creature gets +1/-1.
Whenever equipped creature dies, draw a card. This ability triggers only once each turn.
Equip {1}

Ember Salvo deals 1 damage to target creature and 1 damage to its controller.

Counter target spell, activated ability, or triggered ability. Its controller chooses draw step, main phase, or combat phase. That player skips each instance of the chosen step or phase during their next turn. (Mana abilities can't be targeted.)

When Persecutor of Truths enters, return target creature card with mana value 2 or less from your graveyard to the battlefield.
Once each turn, when you cast a spell from anywhere other than your hand or another nontoken creature you control enters and wasn't cast, you may draw a card.

Spells you cast from anywhere other than your hand can't be countered.
Whenever an opponent casts a spell with the same name as a card they own in exile or in their graveyard, you may draw a card.

Adorned — Commoners' Favored gets +2/+2 as long as it's equipped and/or enchanted.

At the beginning of your end step, create a 1/1 colorless Human creature. Put a sacrifice counter on it.
Creature tokens you control with sacrifice counters on them can't attack or block and have “Sacrifice this creature: Add {C}.”

Disgraced 5 (This enters with five -1/-1 counters. Whenever it deals combat damage to a player, remove all -1/-1 counters from it.)
Prevent all combat damage that would be dealt to Heir Unapparent.

Counter target spell. If that spell is countered this way, its owner puts it on the top or bottom of their library instead of into their graveyard.
Each player draws a card.

Gestalt (When this or another creature you control enters, you may merge it with the one in play, keeping counters and attachments. They become the permanent on top plus all abilities from under it.)
This permanent gets +2/+2 for each card and token merged with it.

All creatures get -3/-3 until end of turn.

Vision (Whenever this or another creature you control enters, reveal the top card of your library. Then you may put that card into your graveyard.)
Whenever Aether Recoverer envisions a creature card, return target noncreature card from your graveyard to your hand.

{T}: Add {C}.
{1}, {T}: Transform Ruined Theater.

[+2]: Add {R}{R}. Until end of turn, red mana doesn't empty as steps and phases end, and creatures you control gain “{R}: This creature gets +1/+0 until end of turn.”
[–3]: You may cast a monocolored red spell with mana value 6 or less from your hand without paying its mana cost.
[–6]: You may pay any amount of {R}. When you do, Amelie Mayn deals that much damage to each of up to that many different targets.

Whenever Cavern Monstrosity attacks, exile the bottom card of your library. You gain life equal to its mana value.