msem-instigator

Slipstream (This creature can't be blocked as long as only creatures with slipstream are attacking.)
{4}{B}{B}, {T}, Sacrifice Abalone Abomination: Create an X/X black Horror creature token, where X is the number of cards in your graveyard.

Choose land or nonland. Reveal cards from the top of your library until you reveal a card of the chosen kind. Put that card into your hand and the rest on the bottom of your library in a random order.

Trample (This creature can deal excess combat damage to the player or planeswalker it's attacking.)
Cycling {G} ({G}, Discard this card: Draw a card.)

This spell costs {2} less to cast if you've cast both an instant spell and a sorcery spell this turn.
Haste

Search your library for a basic land card, reveal it, put it into your hand, then shuffle.
Menagerie — If there are five or more creature types among creatures you control, creatures you control get +1/+1 until end of turn.

Haste
Whenever two or more creatures you control deal combat damage to a player, tap those creatures, then gain control of target creature you don't control until end of turn. Untap that creature. It gains haste until end of turn. After this phase, there's an additional combat phase.

As long as it's your turn, Otto is an Otter Soldier creature with indestructible and “This creature's power and toughness are each equal to twice the number of creatures you control.”
[+1]: Create a 2/2 green and white Otter Soldier creature token.
[–8]: Draw cards equal to the greatest power among creatures you control, then you gain life equal to the greatest toughness among creatures you control.

As an additional cost to cast this spell, discard a card.
Advent from Above deals 3 damage to any target. Exile the top two cards of your library. You may play those cards during any turn you attacked with an artifact creature.

Look at the top five cards of your library. You may reveal a creature card from among them and put it into your hand. Put the rest on the bottom of your library in a random order. If you didn't put a card into your hand this way, draw a card.

Whenever you cast an Adventure spell, put a +1/+1 counter on Adventurer Extraordinaire.

Look at the top eight cards of your library. Put up to two creature cards with mana value 5 or less from among them onto the battlefield under your control. Put the rest on the bottom of your library in a random order.
Menagerie — If there are five or more creature types among creatures you control, if an ability of a permanent you control is triggered this turn, that ability triggers an additional time.

Flying
As long as Aerial Tactician is tapped, Soldiers you control get +0/+1.
As long as Aerial Tactician is untapped, Soldiers you control get +1/+0.

When Alaina enters, each opponent loses X life and you gain X life, where X is the number of Clerics you control.
{W}{B}, Pay 2 life: Return Alaina from your graveyard to your hand. Activate only if you have more life than your starting life total.

Create two 2/1 black and red Cat Pirate creature tokens with menace. You lose 2 life.

{T}: Add one mana of any color.
{4}, {T}, Sacrifice Ancestral Tapestry: Search your library for a legendary card, reveal it, put it into your hand, then shuffle.

Sacrifice a creature. When you do, draw two cards. (Then exile this card. You may cast the creature later from exile.)

You may play Anemone Cluster from your graveyard as long as seven or more cards are in your graveyard.
Anemone Cluster enters tapped.
{T}: Add {G} or {U}.
Cycling {1}{G}{U} ({1}{G}{U}, Discard this card: Draw a card.)

At the beginning of each end step, if you drew and/or discarded six or more cards this turn, return Anemothrys, Reefcrown from your graveyard to the battlefield.
Cycling {R}{G} ({R}{G}, Discard this card: Draw a card.)

Exile the top five cards of your library. You may put a creature card from among them with mana value 2 or less onto the battlefield.

Target creature gets +2/+2 until end of turn. If it's an enchanted creature or enchantment creature, it also gains hexproof and indestructible until end of turn. (It can't be the target of spells or abilities your opponents control. Damage and effects that say “destroy” don't destroy it.)

Draw two cards. You may cast an instant or sorcery spell with mana value X or less from your hand without paying its mana cost, where X is the number of cards in your hand.

Ward—Exile three cards from your graveyard. (Whenever this permanent becomes the target of a spell or ability an opponent controls, counter it unless that player exiles three cards from their graveyard.)
Menagerie — Astralhorn Familiar gets +2/+2 as long as there are five or more creature types among creatures you control.

(Add a quest counter as this enters. Sacrifice after 3.)
At the beginning of your end step, if you cast no spells this turn, add a quest counter.
Untap each creature you control. Until your next turn, they gain “{T}: Scry 1.”
Scry 2, then draw two cards. You gain 2 life.

Flying
At the beginning of your end step, if you cast no spells this turn, scry 2.

Target creature can't block this turn. (Then exile this card. You may cast the creature later from exile.)