msem-instigator

Return target creature card from a graveyard to the battlefield. Then if that card wasn't put into a graveyard from the battlefield this turn, exile it.

Menace
Swampcycling {1}, forestcycling {1} ({1}, Discard this card: Search your libary for a Swamp or Forest card, reveal it, put it into your hand, then shuffle.)

Flash
Flying
When Justiciar Overseer enters, the next 2 damage that a source of your choice would deal to you and/or permanents you control this turn is dealt to any target instead.

Whenever an artifact you control becomes tapped, K-17 Drone deals 1 damage to each opponent.

Flash
Flying

You don't lose the game for drawing from an empty library.
As long as you have seven or fewer cards in each of your libraries, you may cast spells without paying their mana costs.

Kahroba Pureblood has trample as long as it has a counter on it.

Menace
When Kai'Zhou enters, you may have all legendary nonland permanents phase out until your next turn.
Whenever Kai'Zhou deals combat damage to a player, they sacrifice a legendary permanent.

When Kalak Culler enters, each opponent loses life equal to the number of creatures you've sacrificed this turn.
Revive—{3}{B}, Sacrifice a creature. ({3}{B}, Sacrifice a creature, Exile this card from your graveyard: Create a token that's a copy of it except it has no mana cost. Revive only as a sorcery.)

[+1]: Discard a card. If you do, each opponent discards a card and loses 1 life.
[–3]: Destroy target creature or planeswalker.
[–7]: Draw a card for each creature card and planeswalker card in all graveyards. Target opponent loses that much life.

As long as there are seven or more loyalty counters on Kalemn, she has lifelink and deathtouch.
[+2]: Kalemn deals 2 damage to each opponent.
[+1]: Kalemn deals 1 damage to target creature or planeswalker.
[–7]: For each opponent, Kalemn deals 3 damage to that player unless they discard a card. Repeat this process six times.

Enchant creature
When Kalku Initiation enters, you lose 3 life and discard a card.
Enchanted creature gets +3/+2, has ward {2}, and has “Whenever this creature deals damage to a player, draw two cards.”

Whenever Kalro Gritbrawler attacks, if you control a Desert or there is a Desert card in your graveyard, it gains double strike until end of turn.
Desertcycling {2} ({2}, Discard this card: Search your library for a Desert card, reveal it, and put it into your hand, then shuffle.)

Flying, haste
Ward—Pay 3 life.
The first Dragon spell you cast each turn costs {R}{R} less to cast. (This can reduce the amount of generic mana you pay.)

Haste, prowess
Whenever Kamito Warcaster attacks, you may pay {2}{R}. If you do, create a token that's a copy of another target creature you control and that's tapped and attacking. It's a colorless Spirit in addition to its other types. Exile that token at end of combat.

Rhapsody {5}{R}{W} (Pay {5}{R}{W} to cast this as a 4/4, or as a sorcery to make it become a 4/4.)
Whenever a creature you control with power 4 or greater attacks, look at the top four cards of your library. You may cast a nonland card with mana value 3 or less from among them without paying its mana cost. Put the rest on the bottom of your library in a random order.

Deathtouch
When Kaneh Assassin enters, judge another target creature you control. (Honor it by putting a +1/+1 counter on it or condemn it by sacrificing it to draw a card.)

When Kaone enters, if it was cast, exile target instant or sorcery card from your graveyard. If its mana value is less than or equal to the number of spells you've cast this turn, you may cast a copy of that spell without paying its mana cost. If you don't cast a copy this way, put the exiled card into your hand.

{1}{U}{B}, Discard Karaja Hetegex: You may activate one of her loyalty abilities without paying its loyalty cost.
[–1]: Return target artifact, enchantment, or spell to its owner's hand.
[–1]: Target creature gets -2/-2 until end of turn.
[–1]: Scry 1, then draw a card.

Indestructible
As long as your devotion to green and white is less than seven, Karametra isn't a creature.
You may play an additional land on each of your turns.
As you begin searching your library, you may reveal a basic land card from your library and put it into your hand.

Whenever you cast an instant or sorcery spell, choose a counter on target permanent or player. You may put an additional counter of that kind on that permanent or player.

Vigilance
Revive {3}{G} ({3}{G}, Exile this card from your graveyard: Create a token that's a copy of it except it has no mana cost. Revive only as a sorcery.)

First strike
Revive {4}{W} ({4}{W}, Exile this card from your graveyard: Create a token that's a copy of it except it has no mana cost. Revive only as a sorcery.)

Vigilance
Spirited (When this creature enters, you may activate one of its activated abilities without paying its cost.)
{2}{W}{W}: Creatures you control get +1/+1 until end of turn.

Whenever you make first contact, you may activate one of Karina's loyalty abilities. (You make first contact the first time each turn you cast a spell with a name not in your graveyard or control already.)
[+1]: Each player draws a card.
[–2]: Exile target nonland permanent. At the beginning of the next end step, return it to its owner's hand or to the battlefield under its owner's control.
[–7]: You get an emblem with “You may cast spells that don't have the same name as a permanent you control or a card in your graveyard without paying their mana costs.”