msem-instigator

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.)

Deathtouch
When Depthlight Salvager enters, you may salvage a creature card with mana value 3 or less. (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.)

Spells your opponents cast cost {1} more to cast.
Spells you cast cost {1} less to cast.

Concord — When Dolphin Rider enters, if there are four or more card types among permanents you control, you gain 5 life.

Pressure {3}{U}{B} (You may cast this spell for its pressure cost if seven or more cards are in your graveyard.)
Destroy up to one target creature. Return all other nonland permanents to their owners' hands.

Primal—Reappropriate green. (During your turn, you may cast this spell by exiling two green cards from your hand and/or graveyard instead of playing a land.)
When Dovon's Masterwork enters, return target land card from your graveyard to the battlefield tapped.

Enchant opponent
When Down with the Ship enters, enchanted player discards a card unless they sacrifice a creature.
{1}{B}, Sacrifice Down with the Ship: Return target creature card from your graveyard to your hand.

First mate — Twelve or more cards in your starting deck have “gain control” or “exchange control” in their printed rules text. (If this card outside the game is your chosen first mate, you may swap it with a card in your opening hand.)
Dr. Telsi of the Ark can't be blocked.
Dr. Telsi gets +1/+1 for each permanent you control but don't own.

Pressure {3}{U} (You may cast this spell for its pressure cost if seven or more cards are in your graveyard.)
Return target creature to its owner's hand. If this spell was cast for its pressure cost, put that creature into its owner's library second from the top instead.

Instant, sorcery, and Dragon cadence (Whenever you cast an instant, sorcery or Dragon spell, if its mana value is greater than this creature's power, put a +1/+1 counter on this creature.)
{R}, {T}, Discard a card: Draw a card.

Each creature card you own that isn't on the battlefield has madness. The madness cost is equal to its mana cost. (If you discard a card with madness, discard it into exile. When you do, cast it for its madness cost or put it into your graveyard.)
{T}, Discard a card: Dragonlord's Shrine deals 2 damage to any target.

Pressure {G} (You may cast this spell for its pressure cost if seven or more cards are in your graveyard.)
Return target card from your graveyard to your hand. Exile Drawn to the Light.

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.