msem-instigator

This spell costs {1} less to cast for each card put into your graveyard from anywhere this turn.
At the beginning of each player's upkeep, that player loses 1 life, discards a card, and sacrifices a creature.

Flash
If an opponent would draw one or more cards except during their draw step, instead they draw a card and you create that many 1/1 white Bird creature tokens with flying.

Double strike, trample, indestructible, haste
When Dredgeline Colossus enters, salvage up to eight noncreature, nonland cards. (You may exile them 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.)

Creatures you control get +1/+1 until end of turn. Merfolk you control get an additional +1/+1 until end of turn.

When Drop Bear enters, return another target permanent that isn't a land an opponent controls or a card in a graveyard to its owner's hand.

When Dualglaive Acolyte enters, create a green Aura enchantment token named Calamighty attached to target creature. The token has enchant creature and “Enchanted creature gets +1/+1 and can't be blocked by creatures with power 2 or less.”

When Duchess Odelia VII enters, search your library for a nonland permanent card with mana value 1 or less, reveal it, put it into your hand, then shuffle.

Vigilance
Whenever an opponent casts a spell, create a Treasure token unless that player pays {1}, then create a 1/1 white Merfolk creature token unless that player pays {1}.
{W}{U}{B}{R}{G}, {T}: Other creatures you control get +3/+3 and gain vigilance and indestructible until end of turn.

{3}{R}: Target creature can't be blocked this turn if it's an artifact creature or has power 2 or less.

{T}, Sacrifice an artifact or creature: Each opponent loses 1 life and you gain 1 life.

When Dusk Lieutenant enters, forebode. (Create a tapped colorless Omen artifact token with “{T}, Discard a card, Sacrifice this artifact: Draw a card.”)
Once each turn, when you discard a card during your turn, each opponent discards a card.

Equipped creature gets +1/+1 and has double strike.
Equip {2}{R}
Madness {2}{R} (If you discard this card, discard it into exile. When you do, cast it for its madness cost or put it into your graveyard.)
When Dwarven War Hatchet enters, if you cast it for its madness cost, attach it to target creature you control.

{4}{G}{G}: Eager Voyager voyages. (If it isn't blocking or targeted by another spell or ability, it phases out.)
Whenever Eager Voyager phases in, if it has no +1/+1 counters on it, put four +1/+1 counters on it.

Vigilance
Resolute — Whenever East Ward Champion attacks, attacking creatures you control gain indestructible until end of turn if East Ward Champion's power is greater than its base power.

First strike
{1}{R}, Discard a card: East Ward Forgetender gets +2/+0 until end of turn.

Resolute — At the beginning of combat on your turn, East Ward Halberdier gains double strike until end of turn if its power is greater than its base power.

When Edina's Soulsinger enters, create a 1/1 blue Jellyfish enchantment creature token with slipstream. (It can't be blocked as long as only creatures with slipstream are attacking.)

Whenever you cast an artifact or enchantment spell, scry 1, then create a 1/1 white Merfolk creature token.
Whenever you cast a Merfolk spell, look at the top card of your library. If it's an artifact or enchantment card, you may reveal it and put it into your hand.

Elaborate Firecannon doesn't untap during your untap step.
{4}, {T}: Elaborate Firecannon deals 2 damage to any target.
At the beginning of your upkeep, you may discard a card. If you do, untap Elaborate Firecannon.

When Elder Prophesier enters, look at the top five cards of your library. You may reveal a Curse card from among them and put it into your hand. Put the rest on the bottom of your library in any order.

{1}{R}, {T}, Sacrifice an artifact: Elise, Maktali Prodigy deals 2 damage to any target.
{1}{U}, {T}, Sacrifice an artifact: Return target nonland permanent to its owner's hand.
{3}{U}{R}, {T}, Sacrifice three artifacts: Discard your hand, then draw seven cards.

During each of your turns, you may cast a card with a cycling ability from your graveyard by discarding a card in addition to paying its other costs. If that spell would be put into your graveyard, exile it instead.
Cycling {2} ({2}, Discard this card: Draw a card.)

Choose one —
• Create two 1/1 blue Tentacle creature tokens.
• Untap target creature. It gets +2/+4 until end of turn.

Flying
Whenever Empyrean Griffin attacks, up to one target creature voyages. (If it isn't blocking or targeted by another spell or ability, it phases out.)
Permanents your opponents control can't phase in.

Counter target creature spell. You may cast a copy of that spell. (You still pay its costs. The copy becomes a token.)