Return all attacking creatures to their owner's hand.

For each attacking creature, its owner puts it on the top or bottom of their library.

Flying, deathtouch

When Baleful Strix enters the battlefield, draw a card.

You may have Clone enter the battlefield as a copy of any creature on the battlefield.

Whenever a creature you control deals combat damage to an opponent, you may draw a card.

Islandwalk (This creature can't be blocked as long as defending player controls an Island.)

Whenever Colossal Whale attacks, you may exile target creature defending player controls until Colossal Whale leaves the battlefield. (That creature returns under its owner's control.)

Add {B}{B}{B}.

Blue creatures you control can't be blocked.

{2}{U}, {T}, Discard a card, Sacrifice a land: Search your library for up to two basic land cards, put them onto the battlefield, then shuffle.

Destroy all creatures of the creature type of your choice.

{5}{U}{U}: Frilled Sea Serpent can't be blocked this turn.

Destroy six target creatures.

When Hostage Taker enters the battlefield, exile another target creature or artifact until Hostage Taker leaves the battlefield. You may cast that card for as long as it remains exiled, and mana of any type can be spent to cast that spell.

Enchant creature

Enchanted creature has "At the beginning of your upkeep, sacrifice a creature."

Affinity for tokens (This spell costs {1} less to cast for each token you control.)

Whenever a token enters the battlefield under your control, tap target nonland permanent an opponent controls. It doesn't untap during its controller's next untap step.

When Mesmerizing Benthid enters the battlefield, create two 0/2 blue Illusion creature tokens with "Whenever this creature blocks a creature, that creature doesn't untap during its controller's next untap step."

Mesmerizing Benthid has hexproof as long as you control an Illusion.

Whenever an opponent draws a card, you may pay {1}. If you do, draw a card.

Destroy target creature.

Whenever you draw a card, you may pay {1}. If you do, put a +1/+1 counter on Nadir Kraken and create a 1/1 blue Tentacle creature token.

Whenever Nemesis of Reason attacks, defending player mills ten cards.

Until end of turn, each creature target player controls loses all abilities and becomes a blue Frog with base power and toughness 1/1.

Destroy target creature. It can't be regenerated. Its controller creates a 3/3 green Ape creature token.

At the beginning of your upkeep, you may look at the top card of your library. If it's a creature card, you may reveal it and put a quest counter on Quest for Ula's Temple.

At the beginning of each end step, if there are three or more quest counters on Quest for Ula's Temple, you may put a Kraken, Leviathan, Octopus, or Serpent creature card from your hand onto the battlefield.

Destroy target creature. It can't be regenerated. That creature's controller creates a 3/3 green Frog Lizard creature token.

Return all nonland permanents target player controls to their owner's hand.

{T}: Destroy target tapped creature.

Flying

When Runo Stromkirk enters the battlefield, put up to one target creature card from your graveyard on top of your library.

At the beginning of your upkeep, look at the top card of your library. You may reveal that card. If a creature card with mana value 6 or greater is revealed this way, transform Runo Stromkirk.

Flying

Whenever Krothuss, Lord of the Deep attacks, create a tapped and attacking token that's a copy of another target attacking creature. If that creature is a Kraken, Leviathan, Octopus, or Serpent, create two of those tokens instead.

When Scourge of Fleets enters the battlefield, return each creature your opponents control with toughness X or less to its owner's hand, where X is the number of Islands you control.

Mutate {1}{U} (If you cast this spell for its mutate cost, put it over or under target non-Human creature you own. They mutate into the creature on top plus all abilities from under it.)

Flash

Whenever this creature deals combat damage to a player, draw a card.

Krakens, Leviathans, Octopuses, and Serpents you control can't be blocked except by Krakens, Leviathans, Octopuses, and Serpents.

{6}{U}{U}: Monstrosity 4. (If this creature isn't monstrous, put four +1/+1 counters on it and it becomes monstrous.)

When Shipbreaker Kraken becomes monstrous, tap up to four target creatures. Those creatures don't untap during their controllers' untap steps for as long as you control Shipbreaker Kraken.

{T}: Add {C}{C}.

Whenever a Kraken, Leviathan, Octopus, or Serpent you control deals combat damage to a player, create a 9/9 blue Kraken creature token.

Islandwalk (This creature can't be blocked as long as defending player controls an Island.)

All lands are Islands in addition to their other types.

Creatures without flying or islandwalk can't attack.

Tidal Kraken can't be blocked.

Return all permanents of the color of your choice to their owners' hands.

Flying

As long as Wonder is in your graveyard and you control an Island, creatures you control have flying.