So I built the obvious deck and it's breezing through the levels

3 x Opt
4 x Omen of the Sea
4 x Heartless Act
3 x Quench
2 x Negate
4 x Sinister Sabotage

4 x Brineborn Cutthroat
4 x Brazen Borrower
4 x Sea-Dasher Octopus
4 x Cunning Nightbonder
4 x Slitherwisp

4 x Temple of Deceit
4 x Watery Grave
6 x Island
6 x Swamp


The deck clearly has legs but I've only built it today so it's going to need adjusting. Got to Diamond 3 so far and it's still full of jank so I dunno. I'll have to think of SB options for Bo3 too.

More importantly it's a blast to play.

I built it a bit different:
The mutate cards are super good here, the Bat is a must IMO.

Deck
4 x Spectral Sailor
6 x Island
4 x Brineborn Cutthroat
4 x Sea-Dasher Octopus
2 x Brazen Borrower
3 x Unsummon
4 x Swamp
4 x Dirge Bat
4 x Cunning Nightbonder
4 x Slitherwisp
2 x Quench
2 x Heartless Act
3 x Neutralize
4 x Temple of Deceit
4 x Watery Grave
2 x Lore Drakkis
4 x Fabled Passage

Sideboard
4 x Aether Gust
3 x Mystical Dispute
2 x Heartless Act
3 x Negate
3 x Essence Scatter

I dunno, you need the bat on the battlefield, and then an octopus to graft onto it. Or a couple nightbonders on the board so you can cast the bat itself for its mutate cost.Seemed clunky in testing. Even Pouncing Shoreshark performed better for me. Maybe I cut it too soon though.

But it's a decent treat on its own, I run the guys that let's you fetch for cards ok the GY from a total of 10 mutate cards.
If you put and Octopus or Drakis on the Bat your are getting HUUUGe value + some Corona lore bonus points.

I thought it was clunky too now I would not go less than 4.

Oh I didn't notice the Lore Drakkis. That looks like a great idea even without Bats.

I'll go try that, thanks.

Okay so I was wrong and the bat is in. Also Lore Drakkis is awesome.

This is where I'm at:

4 x Omen of the Sea
2 x Quench
3 x Heartless Act
4 x Sinister Sabotage

4 x Brineborn Cutthroat
4 x Cunning Nightbonder
3 x Brazen Borrower
4 x Sea-Dasher Octopus
4 x Slitherwisp
2 x Lore Drakkis
4 x Dirge Bat

4 x Watery Grave
4 x Temple of Deceit
2 x Fabled Passage
6 x Island
6 x Swamp


Sideboard

2 x Noxious Grasp
3 x Mystical Dispute
3 x Aether Gust
2 x Negate
2 x Essence Scatter
3 x Disfigure

So did you manage to make it work?

Got stuck at diamond 4. I think it's T2, T1.5 at best. It's fun though.
Also the lists I've seen now that there are lists all run stonecoil serpent, it's weird.

flashing mutate on a stonecoil is super strong