msem-instigator

[+1]: Create a 1/1 white Warrior creature token. Put a menace counter on it.
[–2]: Draw a card for each tapped creature you control.
[–5]: You get an emblem with “Creature cards in your hand have ‘{1}{U}{B}, Reveal this card from your hand, Return an unblocked attacking creature you control to its owner's hand: Put this card onto the battlefield tapped and attacking.'”

Equipped creature gets +2/+2.
Art of war — At the beginning of your end step, if equipped creature dealt damage to an opponent this turn, you may return target creature card from your graveyard to your hand.
Equip {2}

When Kizoku Valiant enters or dies, you gain 2 life.
Art of war — At the beginning of your end step, if Kizoku Valiant dealt damage to an opponent this turn, put a +1/+1 counter on it.

Whenever one or more other creatures you control enter, upgrade each creature you control. (Give each one of the listed counters it doesn't already have. Upgrades are independent.)
• +1/+1
• Flying
• First strike
• Vigilance
• Lifelink

Whenever Knight of the Hawk deals combat damage to a player, you may sacrifice it. If you do, search your library for a red legendary creature card, reveal it, put it into your hand, then shuffle.

Tap another untapped creature you control: Knight of the Orchards gets +1/+1 until end of turn.

Whenever Knight of the Raven deals combat damage to a player, you may sacrifice it. If you do, search your library for a black legendary creature card, reveal it, put it into your hand, then shuffle.

Whenever Knight of the Staff deals combat damage to a player, you may sacrifice it. If you do, search your library for a blue legendary creature card, reveal it, put it into your hand, then shuffle.

Whenever Knight of the Stag deals combat damage to a player, you may sacrifice it. If you do, search your library for a white legendary creature card, reveal it, put it into your hand, then shuffle.

Whenever Knight of the Verdigris deals combat damage to a player, you may sacrifice it. If you do, search your library for a green legendary creature card, reveal it, put it into your hand, then shuffle.

When Knight's Attendant enters, create a 2/2 white Knight creature token with vigilance.

Enchant creature
When Knight's Daring enters, put two +1/+1 counters on enchanted creature.
Whenever enchanted creature deals combat damage to a player, put a +1/+1 counter on each creature you control with a +1/+1 counter on it.

At the beginning of your end step, if an opponent lost life this turn, Kogane the Crimson Consort deals 2 damage to each opponent and you gain 2 life.

Equipped creature gets +2/+2.
Art of war — At the beginning of your end step, if equipped creature dealt damage to an opponent this turn, create a 1/1 colorless Samurai creature token.
Equip {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.

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.

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

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

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.

{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.

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.

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.)