{T}, Exile cards from your graveyard equal to the number of opponents you have: Target creature card in your graveyard gains encore until end of turn. The encore cost is equal to its mana cost. (Exile the creature card and pay its mana cost: For each opponent, create a token copy that attacks that opponent this turn if able. They gain haste. Sacrifice them at the beginning of the next end step. Activate only as a sorcery.)

Whenever one or more nontoken Merfolk you control become tapped, create a 1/1 blue Merfolk creature token with hexproof.

Persist (When this creature dies, if it had no -1/-1 counters on it, return it to the battlefield under its owner's control with a -1/-1 counter on it.)

Whenever you cast a blue spell, Gravelgill Duo gets +1/+1 until end of turn.

Whenever you cast a black spell, Gravelgill Duo gains fear until end of turn. (It can't be blocked except by artifact creatures and/or black creatures.)

Whenever Hollowsage becomes untapped, you may have target player discard a card.

Inkfathom Infiltrator can't block and can't be blocked.

Fear (This creature can't be blocked except by artifact creatures and/or black creatures.)

{2}{U}{B}: Each unblocked creature has base power and toughness 4/1 until end of turn.

Creatures don't untap during their controllers' untap steps.

Whenever a creature enters the battlefield, untap all creatures.

{T}: Target player exiles a card from their graveyard.

Whenever you cast a black spell, you may untap Merrow Bonegnawer.

{1}{U/B}, {Q}: Target creature gets -2/-0 until end of turn. ({Q} is the untap symbol.)

Deathtouch

When Mire Triton enters the battlefield, mill two cards and you gain 2 life.

At the beginning of each end step, if an opponent lost 3 or more life this turn, you may draw a card. (Damage causes loss of life.)

{T}: Target land becomes an Island until end of turn.

{2}{B}, {T}: Target player discards a card. Activate only as a sorcery.

Protection from green

{T}: Draw a card, then discard a card. If you discarded an instant or sorcery card this way, each opponent loses 1 life and you gain 1 life.

{2}, Sacrifice Vohar, Vodalian Desecrator: You may cast target instant or sorcery card from your graveyard this turn. If that spell would be put into your graveyard, exile it instead. Activate only as a sorcery.

Wanderbrine Rootcutters can't be blocked by green creatures.

Flash

{2}{U}{B}, Return an unblocked attacking Rogue you control to its owner's hand: Put Zareth San, the Trickster from your hand onto the battlefield tapped and attacking.

Whenever Zareth San deals combat damage to a player, you may put target permanent card from that player's graveyard onto the battlefield under your control.