I think the underground needs an update as well...
But if you read my thread, you'd notice that I kind of meant an animal, not a fantasy monster. And I don't think that pictures of Spongebob and somewhere with a lot of water hint at a LOTR-styled update.
Mojang really likes to travel to get sounds for IRL animals they implement into MC.
They recorded actual parrot, dolphin, and panda sounds for 1.12, 1.13, and 1.14 respectively.
Now, Cojomax99 has tweeted that he is somewhere, and he isn't allowed to tell us where or why.
He's probably wherever he is to record new animal sounds.
So, my question was: Where do you think Cojomax99 is, and what animal do think he could be hinting at?