Whenever you cast a spell, if it's the first instant spell, the first sorcery spell, or the first Otter spell other than Alania you've cast this turn, you may have target opponent draw a card. If you do, copy that spell. You may choose new targets for the copy.

Exploit (When this creature enters, you may sacrifice a creature.)

When Diver Skaab exploits a creature, target creature's owner puts it on their choice of the top or bottom of their library.

Undaunted (This spell costs less to cast for each opponent.)

Exile two target creatures. For each of those creatures, its controller reveals cards from the top of their library until they reveal a creature card, puts that card onto the battlefield, then shuffles the rest into their library.

Tap two untapped creatures you control: Tap target creature.

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

When Inkfathom Divers enters, look at the top four cards of your library, then put them back in any order.

Flying

When Junk Diver dies, return another target artifact card from your graveyard to your hand.

Whenever Master of Diversion attacks, tap target creature defending player controls.

Flying

When Merfolk Skydiver enters, put a +1/+1 counter on target creature you control.

: Proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

, Sacrifice Rootwater Diver: Return target artifact card from your graveyard to your hand.

Flying

: Shriekdiver gains haste until end of turn.