msem-instigator

When Jinyu Mirror-Blade enters, you may exchange its base power with another target creature's base power until either leave the battlefield.

Flash
When Mokuteki Ambusher enters, until end of turn, other creatures you control gain “{T}: This creature deals 1 damage to any target.”

Deathtouch, protection from legendary
Vielle, Undercity Wayfarer has all loyalty abilities of permanents on the battlefield that cost +1, +0, or -1. (Before cost changes. Add or remove loyalty counters from Vielle to pay their loyalty costs.)

When Mulchborn Behemoth enters, you may sacrifice any number of lands.
Mulchborn Behemoth gets +1/+1 for each land card in your graveyard.
{B}{G}, Sacrifice a land: Destroy target creature or land.

At the beginning of your upkeep, you may search your library for a permanent card with mana value 1 or less, put it onto the battlefield, then shuffle.

Put target artifact or enchantment with mana value less than or equal to the number of basic lands you control on the bottom of its owner's library.

Reverberate {1}{U} (When you cast this spell, copy it if you paid its reverberate cost. You may choose new targets for the copy.)
Until end of turn, target creature loses all abilities and becomes a blue Elemental with base power and toughness 3/3.

Trample
Bessie's Crusher has haste as long as you control another Wurm.

Exile the top card of your library. You may play that card until the end of your next turn.

Other Rebel creatures you control get +1/+0.
When Youthful Renegade enters, create a 1/1 white Rebel creature token.

Knight spells you cast cost {1} less to cast.

Lifelink
When Pact Equivocator enters, you lose 2 life and draw a card.

Trample
Shapen, Spiteful Creation must be blocked each combat if able.
The first time Shapen, Spiteful Creation would be dealt damage each turn, prevent that damage.

{T}: Add {C}.
At the beginning of each end step, if you control five or more Snake creatures, transform Aghavaan's Wound.

Flying
Whenever you make first contact, Curio Hellkite deals 2 damage to any target. (You make first contact the first time each turn you cast a spell with a name not in your graveyard or control already.)

Flying
When Skymount Reinforcements enters, put a +1/+1 counter on another target creature.

Flying
You pay {0} to cast your first spell each turn rather than its mana cost. If you cast a spell with {X} in its mana cost this way, X is 8.

Enspirit (As you cast this spell, you may exile a nonenchantment creature you control until this leaves the battlefield or fails to resolve. Reduce this spell's cost by the exiled card's mana value.)
At the beginning of your upkeep, create a token that's a copy of the enspirited card. It gains haste until end of turn. Exile it at the beginning of the next end step.

When Kingpin of Nizev enters, create two 1/1 white Soldier creature tokens.
Sacrifice a creature: Each opponent loses 1 life. Surveil 1. (Look at the top card of your library. You may put it into your graveyard.)

Calamitous Rampage deals 5 damage to any target.
Cycling {G} ({G}, Discard this card: Draw a card.)

Whenever you cast an instant or sorcery spell from your hand, put that card onto the battlefield face down as a 2/2 creature instead of putting it into your graveyard as it resolves.
Whenever a face-down creature you control deals combat damage to an opponent, you may exile it. If you do, you may cast it without paying its mana cost.

[+1]: Tap up to one target creature. It doesn't untap during its controller's next untap step.
[–2]: Exile target card from a graveyard. Create a 2/2 blue and black Elemental creature token.
[–7]: You get an emblem with “You may play cards from exile.”

Return target card from your graveyard to your hand. Distribute X +1/+1 counters among any number of creatures you control, where X is that card's mana value. Exile Entropic Harvest.

Revive abilities of cards in your graveyard cost {1} less.
Sacrifice Fallow Grave: Create a 1/1 black Worm creature token.

Return target nonland permanent you control and target nonland permanent you don't control to their owners' hands.