msem-instigator

When Keepsake of Binding enters, exile target creature an opponent controls until Keepsake of Binding leaves the battlefield.
{4}, {T}: Tap target creature with power less than the exiled card's power.

This spell costs {1} less to cast for each permanent you control that's an artifact and/or a token.
When Kellythross's Collector enters, you may return another target nonland permanent to its owner's hand.

[+1]: Create a 1/1 colorless Thopter artifact creature token with flying. It gains lifelink until your next turn.
[–1]: Sacrifice an artifact. If you do, draw two cards.
[–6]: Draw seven cards. Artifact spells you cast this turn cost {2} less to cast.

Enchant land you control
When Kelp Garden enters, mill three cards.
Whenever enchanted land is tapped for mana, add one mana of any color among cards in your graveyard.

Sacrifice Kemono-no-Oni: Return target creature card from your graveyard to your hand.

Spirited (When this creature enters, you may activate one of its activated abilities without paying its cost.)
{2}{R}, {T}: Target creature can't block this turn.

Lifelink
Creature and Aura cards with mana value 3 or less in your graveyard have revive {2}{W/B}. ({2}{W/B}, Exile that card from your graveyard: Create a token that's a copy of it except it has no mana cost. Revive only as a sorcery.)

Nonbasic landwalk (This creature can't be blocked as long as defending player controls a nonbasic land.)
Art of war — At the beginning of your end step, if Kenshiro's Cavalry dealt damage to an opponent this turn, put a +1/+1 counter on it.

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, untap up to three target lands you control.
Equip {2}

Enchant player
At the beginning of enchanted player's upkeep, that player chooses draw step, main phase, or combat phase. They skip each instance of the chosen step or phase this turn.

Flying, ward {2}
The first noncreature spell you cast each turn costs {X} less to cast, where X is your devotion to blue. (Each {U} in the mana costs of permanents you control counts toward your devotion to blue.)

Indestructible
As long as your devotion to blue and red is less than seven, Keranos isn't a creature.
Whenever you cast an instant or sorcery spell, you may copy that spell. Do this only once each turn. You may choose new targets for the copy.

Kernel Barrage deals damage to target creature or planeswalker equal to the number of spells you've cast this turn (including this one).
Flashback {2}{R} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Enchant opponent
Creatures attacking enchanted player get +2/+0.
{R}, Discard Kernel Flare: Draw a card.

Whenever you cast a spell, if you sacrificed permanents, discarded cards, and/or paid life as an additional cost to cast it, Kernel Knot deals 2 damage to any target. (Sacrificing permanents for mana doesn't count.)

This spell has flash as long as you control another enchantment.
When Kernel Quarantine enters, exile all other creatures until Kernel Quarantine leaves the battlefield.

You gain 3 life.
Conjure a card named Data-Point into your hand. (It's a sorcery that costs {2} with “Draw a card.”)

Equipped creature gets +3/+2.
Equip enchantment creature {1}
Equip artifact creature {2}
Equip {3}

Flying, deathtouch
Whenever you cast an instant or sorcery spell, return target creature card from your graveyard to the battlefield.

Equipped creature gets +2/+2.
Whenever equipped creature attacks, you may return target creature card with mana value 2 or less from your graveyard to the battlefield.
Equip {2}

Choose two —
• Each opponent sacrifices a creature.
• Each player discards two cards.
• All creatures get -1/-1 until end of turn.
• You draw two cards and you lose 2 life.

Until end of turn, you may play cards from your graveyard by paying 2 life in addition to those cards' costs.
If a card would be put into your graveyard from anywhere this turn, exile that card instead.

Enchant opponent
Whenever enchanted player is attacked, up to one target attacking creature gains menace and lifelink until end of turn.

Puzzlebox (Begin the game with this and another card you own from outside the game in the command zone, locked. That card is face down until you unlock this.)
{5}: Unlock Key to the Nexus. If {W}{U}{B}{R}{G} was spent to activate this ability, you may cast the revealed card without paying its mana cost. Otherwise, put that card on top of your library.

At the beginning of combat on your turn, untap target land. If that land is an Animus, it becomes a creature and gains haste until end of turn.