msem-instigator

When Cosmonaut Pioneer enters or leaves the battlefield, choose one—
• Scry 1, then draw a card.
• Create a 3/3 green Alien creature token with trample.
• You gain 5 life.

This spell can't be countered.
Coppergild Mercenary has hexproof as long as it has one or more counters on it.
Persist (When this creature dies, if it had no -1/-1 counters on it, return it to the battlefield under its owner's control with a -1/-1 counter on it.)

This spell costs {1} less to cast for each creature you control.
Trample
While you're searching your library, you may cast Camouflaged Sprareos from your library.

{1}{G}{G}, Sacrifice a creature: Search your library for a creature card with mana value X or less, where X is 1 plus the sacrificed creature's mana value. Put that card onto the battlefield, then shuffle. Activate only as a sorcery.

Reach, trample
Whenever this creature transforms into Flourishing Companion or attacks, untap all lands you control.

Experience (Whenever this creature attacks, if it has fewer than three +1/+1 counters on it, put a +1/+1 counter on it.)
When Budding Companion has three or more +1/+1 counters on it, remove them all and transform it.

When Bessie's Brood enters, it fights target creature. (If there are no other creatures, it eats itself.)

You may put a creature or planeswalker card from your hand onto the battlefield. It gains haste. Sacrifice it at the beginning of the next end step. Whenever an ability of that permanent is activated this turn, you may copy that ability. You may choose new targets for the copy.

Winnow (Damage dealt to this creature also causes you to lose that much life.)
Whenever Vicious Slasher attacks, target creature gains winnow until end of turn.

Kicker {1}{R} (You may pay an additional {1}{R} as you cast this spell.)
Shal'Draen's Rage deals 1 damage to each creature. If this spell was kicked, it deals 3 damage to each creature instead.

Whenever one or more creatures you control deal combat damage to a player, you may discard a card. If you do, draw a card.
{2}{R}, {T}, Exile two cards from your graveyard: Sarrutu Flamebinder deals 2 damage to any target.

At the beginning of combat on each of your turns, you may sacrifice a land or exile a land card from your graveyard. If you do, create two 1/1 red Goblin creature tokens with haste. Exile those tokens at the beginning of the next end step.

When Reprising Bard enters, exile target instant or sorcery card with mana value 3 or less from your graveyard. When Reprising Bard is no longer on the battlefield, copy the exiled card. You may cast the copy without paying its mana cost.

Each player sacrifices three lands. Regal Ignition deals 3 damage to each nonlegendary creature.

Obscoriate deals 4 damage to target creature or planeswalker. The next time that permanent would die this turn, instead put a basalt counter on it, it becomes a Mountain land named Charred Remains, loses all other card types, and gains “At the beginning of your upkeep, Charred Remains deals 1 damage to you.” (It has “{T}: Add {R}” and loses abilities it already had.)

Whenever you cast an instant or sorcery spell, create a 1/1 red Alien creature token with “This creature can't block.”
{2}{R}, Sacrifice two Aliens: Copy target instant or sorcery spell you control. You may choose new targets for the copy.

(As you complete a condition, decode it. After all are decoded, you solve the mystery and transform this.)
When Mystery of the Crashed Craft enters, create two 1/1 red Alien creature tokens with “This creature can't block.”
{MG}—You cast an instant spell.
{MG}—You cast a sorcery spell.

[+1]: Add {W}{U}{B}{R}{G}.
[–1]: Exile the top three cards of your library. Until end of turn, you may play cards exiled with this permanent.
[–3]: Create a 5/5 Archon creature token that's all colors and has flying and “When this creature enters, it deals 5 damage to any target.”

Chosen one ({W}{U}{B}{R}{G}: Transform this permanent.)
[+2]: Exile the top two cards of your library. Until end of turn, you may play one card exiled with this permanent.
[+1]: Exile up to two cards from your hand, then draw that many cards.
[–3]: Menna, Servant to None deals 3 damage to up to one target player and up to one target creature or planeswalker.

At the beginning of your upkeep, exile the top card of your library. Masahita, Bloodtongue deals damage to you equal to that card's mana value. Until end of turn, you may play that card.

When Kinken, the Dragon's Breath enters, draw a card, then choose a creature card name.
Whenever a creature you control with the chosen name attacks, you may pay {1}. If you do, create a token that's a copy of it and that's tapped and attacking, except it isn't legendary. Exile the token at the beginning of the end step.

Kinjiru Assailant has haste as long as an opponent controls a nonbasic land.

Flying, haste
At the beginning of each of your postcombat main phases, you may cast an instant or sorcery card from your graveyard with mana value less than or equal to the number of creatures that dealt combat damage to opponents this turn without paying its mana cost. If that spell would be put into a graveyard, exile it instead.

Flying
Whenever Herald of Flame attacks, gain control of target permanent until end of combat. If it's a creature, you may have it become tapped and attacking.
Whenever a creature you control becomes blocked, Herald of Flame deals 3 damage to the player or planeswalker that creature is attacking.

Whenever Grin, Scourge of Goresand attacks, when you next cast an instant or sorcery spell with mana value 3 or less this turn, copy that spell. You may choose new targets for the copy.
Dash {2}{R} (You may cast this spell for its dash cost. If you do, it gains haste, and it's returned from the battlefield to its owner's hand at the beginning of the next end step.)