How do I make goop?

[Jeff]

I found my way to the island and let one fish rot for goop. I hear this is used for glue?

Is there anything else that can create goop? Would like to find an efficient way to make more, especially on the mainland.

[Other]

Goop mostly comes from rotting food on the island, and certainly that is the best way to get it if you need lots (set up a bunch of greenhouses and just ignore the produce until it rots). It can (rarely) show up on the mainland as a monster drop, especially through the portal. I don't recall offhand if any of the fights triggered by exploring locations like mountains can drop it or not, but even if they can, you get so many more fights on a portal jaunt that the portal will be faster.

[Morsk]

Frog Man can drop goop. It's how I've gotten it before going to the island.

It is almost useless. There is a glue recipe but goop is not in it; goop is only used for Dustbin, a way of destroying cards without selling them, which is useless before endgame. I can't imagine ever needing more than 2 goop, one on the mainland and one on the island.

[Jeff]

Yeah I didn't realize that goop isn't part of the glue recipe. I just assumed it is for some reason.

Now I learned the dustbin and glue recipes...and trashed my goop. Just trying to build each thing once before starting a second run.