msem-instigator

At the beginning of each player's upkeep, that player loses 2 life unless they sacrifice a creature.
{4}{G}: Create a 2/2 green Wolf Elemental creature token.

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.

{T}: Add {C}.
{T}: Add {C}{C}. Spend this mana only to cast artifact spells. Activate only if you control three or more artifacts.

[+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.

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.

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}

Enchant creature
Enchanted creature gets +2/+2.
{4}{G}: Return Kernon's Consecration from your graveyard to the battlefield attached to target creature you control. Activate only as a sorcery.

[+1]: Mill two cards. Untap up to one target creature or land.
[–2]: Return target creature or land card from your graveyard to your hand.
[–X]: You may sacrifice a creature. If you do, search your library for a creature card with mana value X or less, put it onto the battlefield, then shuffle.

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.

Play with the top card of your library revealed.
You may play lands from the top of your library.
At the beginning of your upkeep, if you control fifteen lands with different names, you win the game.

Cast Khalizors' Last Stand only during your postcombat main phase.
Gain control of target creature until end of turn. Untap all creatures you control. They gain haste until end of turn. After this phase, there is an additional combat phase followed by an additional main phase.

Target creature gets +1/+3 until end of turn.

Destroy target attacking creature.

When Kill This Love enters, target opponent sacrifices a creature.
At the beginning of each end step, if a creature died this turn, you gain 2 life.