msem-instigator

Flash
Flying
When Laughing Bird enters the battlefield, you may return a creature you control to its owner's hand.

As an additional cost to cast this spell, exile a card from your graveyard.
Counter target spell with mana value less than or equal to the exiled card's mana value.

Look at the top three cards of your library. Put one of them into your hand. Put Lost in Deep Storage and the rest on the bottom of your library in any order.

Codex — Unraveling; Unraveling; Unrelenting; Unrelenting; Mindrip; Swipe Secrets. (As this enters, conjure its contents into a shuffled face-up additional library.)
Flash
When Mei's Collection enters the battlefield, draw a card from its codex.

{B}{G}{U}: Mother Roo gets +2/+2 and gains flying until end of turn.

Enchant player
Whenever enchanted player becomes the target of a spell or ability they don't control, if it isn't a copy, its controller copies it.

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}.”

Whenever Path Lighter deals combat damage to a player, it explores. (Reveal the top card of your library. Put it into your hand if it's a land. Otherwise, put a +1/+1 counter on this creature, then you may put that card in your graveyard.)

Target creature can't be blocked this turn. It explores. (Reveal the top card of your library. Put it into your hand if it's a land. Otherwise, put a +1/+1 counter on that creature, then you may put that card in your graveyard.)

Flying
Dragon spells and Adventure spells you cast cost {1} less to cast.

Seaside Skimmer can't be blocked if you've cast a Dragon spell or Adventure spell this turn.

Whenever you cast a noncreature spell, Shiverpass Taskmage explores. (Reveal the top card of your library. Put it into your hand if it's a land. Otherwise, put a +1/+1 counter on this creature, then you may put that card in your graveyard.)

Ward {2}
Slippery Bunyip can't be blocked except by creatures with Adventures.

Tap up to two target permanents. They don't untap during their controller's next untap step. You may put Snooze into its owner's library third from the top.

Enchant artifact or creature
Enchanted permanent doesn't untap during its controller's untap step.
Whenever you make first contact, scry 1.

Exile target artifact, creature, or enchantment. Return that card to the battlefield under its owner's control at the beginning of the next end step.
Draw a card.

Whenever you make first contact, target creature you control can't be blocked by Humans this turn. (You make first contact the first time each turn you cast a spell with a name not in your graveyard or control already.)

End the turn. If it's an opponent's turn, they take an extra turn after this one. (Exile all spells and abilities from the stack, including this card. The player whose turn it is discards down to their maximum hand size. Damage wears off, and “this turn” and “until end of turn” effects end.)

Draw three cards. Then discard two cards unless you discard a card that has the same name as a permanent you control or a card in your graveyard.

Whenever a creature you control attacks and isn't blocked, it explores. (Reveal the top card of your library. Put it into your hand if it's a land. Otherwise, put a +1/+1 counter on that creature, then you may put that card in your graveyard.)

Equipped creature gets +1/+1.
Whenever equipped creature attacks, tap up to one target creature.
Equip {1}

Ward {2} (Whenever this creature becomes the target of a spell or ability an opponent controls, counter it unless that player pays {2}.)
Whenever you cast a spell during an opponent's turn, tap target nonland permanent.

Whenever you cast a spell, you may pay {1}. If you do, Wizened Tortle explores. (Reveal the top card of your library. Put it into your hand if it's a land. Otherwise, put a +1/+1 counter on this creature, then you may put that card in your graveyard.)

Death knell — Each opponent loses 1 life. You gain life equal to the amount of life lost this way. (As a creature you control dies, trigger one death knell of that creature or another permanent you control.)
Whenever a creature dies, trigger a death knell of a permanent you control.

Enchant player
At the beginning of enchanted player's upkeep, if they control two or more creatures and/or planeswalkers, they sacrifice a creature or planeswalker.