msem-instigator

Creatures you don't control get -1/-0 as long as their controller is cursed.

When Delugic Surger enters, if you control another Elemental, return target instant or sorcery card from your graveyard to your hand.

Delusional Noble enters with a -1/-1 counter on it.

When Delusive Shadows enters, each opponent loses life equal to the number of cards that player owns in exile.

(As this Saga enters and after your draw step, ad a lore counter. Sacrifice after III.)
I, II — Create a Treasure token. (It's an artifact with “{T}, Sacrifice this artifact: Add one mana of any color.”)
III — You may sacrifice any number of artifacts. If you do, draw that many cards.

Up to three target creatures can't block this turn.
Menagerie — If there are five or more creature types among creatures you control, exile the top three cards of your library. You may play one of those cards until the end of your next turn.

Target creature gets +5/+5 until end of turn.
Fabled {4}{G} (Then if you cast this for its fabled cost, put it onto the battlefield transformed attached to that creature.)

At the beginning of each player's end step, that player sacrifices a permanent.

Whenever an opponent casts a spell, harmonize. (Trigger up to one harmony of a permanent you control.)
Harmony — Spells your opponents cast cost an additional 2 life to cast until your next turn.

Target player discards two cards.
Cycling {2}{B} ({2}{B}, Discard this card: Draw a card.)
When you cycle Dementia's Clutch, target player discards a card.

Destroy target artifact or land.

{1}{B}, Sacrifice another creature: Draw a card and create an Idol token. (It's an artifact with “{1}, Sacrifice this artifact: Put a +1/+1 counter on target creature. Activate only as a sorcery.”)
{2}{B}, Sacrifice three Idols: Return Demon of Hubris from your graveyard to the battlefield. Activate only as a sorcery.

Create a 4/4 black Demon creature token with flying. You lose 3 life for each Demon you control.
Tether (Then if you cast this from your hand, you may exile it tethered to a creature you control. When it dies, you may cast this from exile without paying its mana cost.)

When Demonqueller Mage enters, gain control of target creature with power 2 or less until Demonqueller Mage leaves the battlefield.

Submerge target artifact or enchantment. (To submerge a card, exile it, then put it on the battlefield face down under its owner's control as a 2/2 creature.)

Tap up to two target creatures.
Cycling {1}{U} ({1}{U}, Discard this card: Draw a card.)
When you cycle Denied Attempt, you may tap target creature.

Create three 1/1 colorless Servo artifact creature tokens.

{T}, Exile a card from your graveyard: Add {B}.

Flying
When Depraved Imp enters, if you control a legendary creature, put two +1/+1 counters on Depraved Imp.

Flash

Whenever you draw your second card each turn, create a 1/1 blue Tentacle creature token.
{3}{G}, Sacrifice two creatures: You gain 1 life and draw a card. Activate only during your turn.

{4}{B}: Depthlight Beacon gets +1/+1 and gains lifelink until end of turn.
Cycling {2/B} ({2/B}, Discard this card: Draw a card.)

When Depthlight Brute enters, if you control three or more artifacts, each opponent loses 3 life and you gain 3 life.

Menace
Other artifact creatures you control have menace.
{2}{B}{R}: Salvage an artifact or creature card. (Exile one from your graveyard until this creature leaves the battlefield. Whenever this creature deals combat damage to a player, put a card it salvaged into your hand.)

Trample
When Depthlight Frontliner enters, you may salvage up to one instant card and up to one sorcery card. (Exile those cards from your graveyard until this creature leaves the battlefield. Whenever this creature deals combat damage to a player, put a card it salvaged into your hand.)