msem-instigator

This spell costs {X} less to cast, where X is 20 minus your life total.
First strike, menace, trample

Cryptic Reef enters tapped.
{T}: Add {G} or {U}.
{2}{G}{U}, {T}, Sacrifice Cryptic Reef: Draw a card.

Escalate {B}{B} (Pay this cost for each mode chosen beyond the first.)
Choose one or more. You may choose the same mode more than once.
• Destroy target creature.
• Target player draws two cards and loses 2 life.

Flying
Whenever one or more counters are put on a creature you control, Curio Siren gets +1/+0 until end of turn.

Flying
Whenever DC-4 Cutie enters or attacks, choose target creature card with mana value 3 or less in your graveyard. You may cast it this turn.
Crew 2

Vigilance, reach
When DL-19 Reject enters, target creature you control gets +2/+2 until end of turn.

Flying
Heroic — Whenever you cast a spell that targets Dawnbringer Vanguard, tap target creature an opponent controls.

Target creature gets -4/-0 until end of turn.
Crystallize. (Put a +1/+1 counter on a creature you control or create a Treasure.)

Put target permanent on top of its owner's library.

When Debaser of Truth enters, if you control three or more Horrors, each opponent discards two cards.
Other Horror creatures you control get +1/+1.

Whenever Defective Abomination attacks, you may sacrifice a permanent. If you do, put a +1/+1 counter on it. It gains indestructible until end of turn.

Whenever you scry, tap target creature an opponent controls.
{2}{W}{U}: Scry 1. You gain 1 life.

Ward {2} (Whenever this creature becomes the target of a spell or ability an opponent controls, counter it unless that player pays {2}.)
Each creature you control with a counter on it has ward {2}. (If a creature has multiple instances of ward, each triggers separately.)

Renown 1 (When this creature deals combat damage to a player, if it isn't renowned, put a +1/+1 counter on it and it becomes renowned.)
When Demolitionist Deviser dies, it deals damage equal to its power to any target.

Create three 1/1 colorless Servo artifact creature tokens.

Counter target nonenchantment spell.

Desperate Android enters tapped.
Whenever another artifact you control dies for the first time each turn, return Desperate Android from your graveyard to your hand.

Target creature you control deals damage equal to its power to target creature or planeswalker you don't control. Scry 1.

{2}, {T}: Exile target creature. Return that card to the battlefield under its owner's control at the beginning of the next end step. Activate only as a sorcery.

Flying, haste
{2}{B}: Devourer of Dread gets +1/+1 until end of turn. If there are three or more creature cards in your graveyard, put a +1/+1 counter on Devourer of Dread instead.

You may cast spells as though they had flash.
Whenever you cast a sorcery spell, each opponent loses 3 life unless they discard a card or sacrifice a nonland permanent.

Flying
Ward—Pay 2 life. (Whenever this creature becomes the target of a spell or ability an opponent controls, counter it unless that player pays 2 life.)
Whenever Dire Harpies of Odunos or another creature with flying you control enters, each opponent loses 1 life and you gain 1 life.

Chronicle (As this enters and after your draw step, add a lore counter. Stop after III.)
[Lore I-II] Until your next turn, up to one target creature can't attack or block and its activated abilities can't be activated.
[Lore III] Target opponent skips their next combat phase.

Doom deals 3 damage to any target and you gain 3 life.
Reconstruct {3}{B}{B} (You may cast this from your graveyard for its reconstruct cost reduced by the mana value of a permanent you sacrifice as you cast it this way. Then exile this.)
You may cast Doom from exile by paying {4}{B}{B}{B} rather than its mana cost. If you do, shuffle it into your library instead of putting it anywhere else as it resolves.

Deathtouch
When Doomed Explorer dies, create a Treasure token. (It's an artifact with “{T}, Sacrifice this artifact: Add one mana of any color.”)