msem-instigator

[+2]: Look at the top card of your library. If it's a permanent card with mana value less than the number of lands you control, you may put it onto the battlefield.
[–1]: Sacrifice a land. If you do, draw three cards.
[–7]: Destroy up to X target permanents, where X is the number of lands you control.

Art of war — At the beginning of your end step, if Kowareta Informant dealt damage to an opponent this turn, draw a card, then discard a card.

Art of war — At the beginning of your end step, if Kowareta Scrounger dealt damage to an opponent this turn, you may search your library for an artifact card, reveal it, put it into your hand, then shuffle.

Lifelink
When Kragma Eviscerator enters, it deals 2 damage to target creature or planeswalker you don't control. Then destroy that creature or planeswalker if you control a creature with power greater than its base power.

{T}: Add {R}.
{R}, {T}: Target creature gains haste until end of turn.

Destroy target land. Create a 1/1 red Goblin creature token.

First strike, haste
Whenever Kragnoss' Battlecharger attacks, it gets +1/+0 until end of turn for each attacking creature.

Haste
When Kragnoss, Rebellion Commander enters, create a 1/1 red Goblin creature token.
Whenever a Goblin you control attacks, Kragnoss, Rebellion Commander deals 1 damage to target creature defending player controls.

Flying
Whenever an opponent discards a card, you may exile it. If you do, create a 1/1 black Bird creature token with flying and “This creature can't block.”
{B}, Sacrifice three Birds: You may cast a card exiled with Krahen, Dusk's Call without paying its mana cost.

Bestow {1}{G}{W}{U} (If you cast this card for its bestow cost, it's an Aura spell with enchant creature. It becomes a creature again if it's not attached to a creature.)
Krikam, the Wanderer and enchanted creature have protection from nonenchanted creatures.

Concord — You may cast this spell as though it had flash if there are four or more card types among permanents you control.
When Krill-Clan Guardian enters, it fights up to one other target creature. If that creature would die this turn, return it to its owner's hand instead.

Krismite Shard enters tapped.
{1}, {T}, Sacrifice Krismite Shard: Aetherize target creature you control. (To aetherize, create a token that's a copy of it, then exile that token.)

{3}{B}{B}: Return target Zombie creature card from your graveyard to the battlefield.
Whenever another creature you control enters from a graveyard or you revive a creature token, that creature gets +2/+0 and gains haste and menace until end of turn.

(Transcend as a sorcery to gain that type and a +1/+1 counter.)
When Kui Mu Lang enters, exile a card from your graveyard. When you do, Kui Mu Lang deals damage equal to that card's mana value to up to one target creature or planeswalker.
{2}{R}: Demigod — Exile your hand, then draw three cards.
{4}{R}{R}: God — Cast any number of cards exiled with Kui Mu Lang without paying their mana costs.

When Kula's Disciple dies, put it on the bottom of its owner's library.

This spell costs {1} less to cast for each creature type among creature cards in your graveyard.
Deathtouch
{1}{B}, Exile any number of creature cards from your graveyard with five or more different creature types among them: Search your library for a card, put it into your hand, then shuffle. Activate only as a sorcery.

Sacrifice Kumo-no-Oni: Prevent all combat damage that would be dealt this turn.

Whenever you cast a spell with mana value greater than the number of loyalty counters on Kunal, Dragonclaw's Legacy, put a loyalty counter on him.
[0]: Until end of turn, Kunal becomes a Monk creature with haste, indestructible, and “Kunal's base power and toughness are each equal to the number of counters on him.”
[–2]: Return target card from your graveyard to your hand.

Flash
Spirited (When this creature enters, you may activate one of its activated abilities without paying its cost.)
{1}: Remove target attacking creature you control from combat and untap it.

Target creature you control gets +3/+1 and gains trample until end of turn.
Showcase {3}{R}{R} (Then if you cast this for its showcase cost, create a 1/1 red Bard creature token that can't block and exile this. Whenever it attacks, you may cast a free copy of this.)

Art of war — At the beginning of your end step, if Kurayami Butcher dealt damage to an opponent, you may destroy target creature that was dealt damage this turn.

Whenever another nontoken creature you control dies, you may exile it. If you do, create a 2/2 colorless Spirit creature token.

Art of war — At the beginning of your end step, if Kurayami Ronin dealt damage to an opponent this turn, you draw a card and you lose 1 life.

{T}: Add {C}.
Tap an untapped creature you control: Kurayami Shrine becomes a 1/1 Spirit creature with deathtouch until end of turn. It's still a land.

Art of war — At the beginning of your end step, if Kuryu Swordsman dealt damage to an opponent this turn, you may have Kuryu Swordsman fight target creature you don't control. (Each deals damage equal to its power to the other.)