msem-instigator

When Journey to Elrayin enters, journey, then choose a creature card name. (To journey, exile the top card of your library face up. Whenever a creature you control deals combat damage to a player, put a journeyed card you own into your hand.)
Whenever a creature you control with the chosen name deals combat damage to a player, journey.

Detain target creature. (Until your next turn, that creature can't attack or block and its activated abilities can't be activated.)
Scry 1.

Target player sacrifices a legendary creature or planeswalker.

Prowess
You may activate inscribe abilities from your graveyard as though they were in your hand.

Kamito Pathseeker can't block.
{3}{R}, Exile Kamito Pathseeker from your graveyard: Return target instant or sorcery card from your graveyard to your hand.

Whenever you cast a noncreature spell, you may pay {R}. If you do, untap Kamito Rageweaver.
{T}: Kamito Rageweaver deals 1 damage to target player.

{T}: Kanaan Wardriver deals 1 damage to target creature you control. That creature gains haste until end of turn.

When Kaneh Headdress enters, create a 1/1 blue Advisor creature token, then scry 1.
Equipped creature gets +1/+1.
Equip {2}

Target player discards a card.
Amass Soldiers 1. (Put a +1/+1 counter on an Army you control. It's also a Soldier. If you don't control one, create an 0/0 black Soldier Army creature token first.)

Exile target creature or planeswalker. Its controller may search their library for a creature or planeswalker card and reveal it, then shuffle and put that card on top.

Whenever Karoa, His Roaring Grace deals combat damage to a player, if he's not equipped, create a colorless Equipment artifact token named Banner attached to him. The token has equip {1} and “Equipped creature gets +1/+1.”

Flash
Enchant creature
Whenever enchanted creature becomes the target of an ability or spell you don't control or leaves the battlefield, enchanted creature deals 3 damage to any target.

{1}{G}: Keen Seafarer voyages. (If it isn't blocking or targeted by another spell or ability, it phases out.)
Whenever Keen Seafarer phases in, put a +1/+1 counter on it.

{T}: Scry 1.
{1}{U}, {T}: Reveal the bottom card of your library. If it's an artifact or enchantment card, put it into your hand.

Target creature gets -4/-0 until end of turn.
Flashback {U} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

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.)

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

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

Kinjiru Assailant has haste as long as an opponent controls a nonbasic land.

Prowess
Whenever Knight-Academic attacks, scry 1.

Konoe's Lieutenant gets +1/+1 as long as an opponent controls a legendary permanent.

Experience (Whenever this creature attacks, if it has fewer than three +1/+1 counters on it, put a +1/+1 counter on it.)
Remove a +1/+1 counter from Kor Skyknight: It gains flying until end of turn.

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.

{4}{W}: Tap target creature.