msem-instigator

Creatures you control have protection from legendary. (Those creatures can't be blocked, targeted, dealt damage, or enchanted by anything legendary.)

Flying
Whenever you cast a spell, exile the top card of your library.
At the beginning of your end step, put a card exiled with Korephyr, Riddle Sage into its owner's hand. Put each other card exiled with Korephyr on the bottom of its owner's library in a random order.
{3}{U/B}: Scry 2.

Kicker {X} (You may pay an additional {X} as you cast this spell.)
When Korrinary Warcaller enters, if it was kicked, search your library for a Rebel permanent card with mana value X or less, put it onto the battlefield, then shuffle.

Play with the top card of your library revealed.
You may cast creature spells from the top of your library. You may cast Centaur spells this way without paying their mana costs.

Koth's Retaliation deals 4 damage to target creature. When that creature dies this turn, exile its controller's graveyard.

[+1]: Search your library for a Mountain card, reveal it, put it into your hand, then shuffle.
[–2]: Koth, One True Hero deals damage to target creature equal to the number of Mountains you control.
[–7]: Create X 3/1 red Elemental creature tokens with trample and haste, where X is the number of Mountains you control.

Other creatures you control get +1/+1.
When Kotis, Promised General dies, you may return it to its owner's hand.

Archive 5 (As this enters, shuffle the top five cards of your main library into a new face up library. Sacrifice this after the archived library is empty.)
Sacrifice a land: Put a card from the archived library into your hand.

[+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.

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.

Menace
When this creature dies, create two tapped 3/2 colorless Eldrazi creature tokens. Put a stun counter on one of them.

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.

Indestructible
As long as your devotion to green and blue is less than seven, Kruphix isn't a creature.
Spells you cast from anywhere other than your hand cost {2} less to cast.
At the beginning of your upkeep, if there are no cards exiled with Kruphix, exile the top card of your library face down. You may look at and play that card for as long as it remains exiled.

{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 (Activate as a sorcery to gain the next 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.

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.

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.