msem-instigator

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.

Whenever you cast a creature spell, create an Idol token. (It's an artifact with “{1}, Sacrifice this artifact: Put a +1/+1 counter on target creature. Activate only as a sorcery.”)
Whenever you sacrifice an Idol, draw a card.

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.

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.

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

Whenever Krallenhorde Instigator deals combat damage to a player, create a 2/2 green Wolf creature token.
At the beginning of your end step, if Krallenhorde Instigator didn't attack this turn, transform it.

Menace
You may spend mana as though it were mana of any color to cast double-faced spells or activate abilities of double-faced sources.
Once during each of your turns, you may cast a double-faced spell you own from outside the game.

This spell can't be countered.
Whenever another nontoken creature you control dies, return it to its owner's hand at the beginning of the next end step.
{6}{G}: Transform Krendel of Kessig. Activate only if it's attacking.

Creature spells you cast can't be countered.
Whenever another nontoken creature you control dies, if it didn't have a +1/+1 counter on it, return it to the battlefield under your control with a +1/+1 counter on it.
At the beginning of your end step, if Krendel, Krallenhorde Alpha didn't attack this turn, transform it.

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.

Once each turn, when you sacrifice a land, you may add one mana of any color. Until end of turn, you don't lose this mana as steps and phases end.

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.)

{T}: Add {C}.
When Krismite Vault is put into a graveyard from the battlefield, create a tapped colorless artifact token named Mox Krismite with “{T}: Add one mana of any color.”