Blobfish

The blobfish is a common enemy found in the Dark Depths.

Description
The Blobfish is a deep sea fish of the family Psychrolutidae. Notably, once inside the submarine, it will decompress, leaving it looking like a gelatinous, fat mass and making it unable to move at all, only being capable of vomiting, presumably due to the internal damages suffered from the decompression. It is notable, however, that even outside the submarine, it has some characteristics of a decompressed blobfish. This was possibly done to make it easier to identify that the creature is a blobfish, since its decompressed appearance is much more well known and memorable than its normal one.

Behavior
It will chase the sub, but it's very slow. Once close enough it will breach the sub creating a single hole. Inside the submarine the blobfish will perpetually vomit, and touching the vomit causes Sea Sickness. The blobfish does not attack the players. The blobfish also serves as a huge obstacle inside the sub, as it's hard to pass. Even after death the corpse retains collision for a few seconds.

Trivia

 * For a while, a bug impeded the blobfish from vomiting. During that time, many players kept them as pets. It was later fixed in the Ramming Crate Update.
 * The blobfish are considered great pets by the Sentient Lampreys.