Yeah, news to me, I'm not a tcg guy, but a seamonster lurking under a boat is probably as cliche as possible, as far as monsters go :)
I hope the scale cues read correctly, it's meant to be a completely normal sized fish and a tiny boat.
Probably unintentional, but this reminds me a lot of an old MTG card called "Dandan" which had a similar vibe! Really fun use of the boat and lily pad for perspective purposes.
Cute and scary at the same time.