I found a possible name. At about the 1:06:00 mark in this video showcasing Debug Mode (which I was unable to view the first time), the question is asked. I believe that's the voice of Simon Thomley (Stealth) responding, "We call it Jellies!" LinkTheLefty (talk) 05:58, December 15, 2013 (UTC)
All right. I gave that a shot, and...
... I don't really like how it turned out - the tentacles bug me and it's not pixel-perfect at all. Use this version at your own discretion, I suppose, although I'd prefer the current image until someone with better skills / access to more resources can pull it off. Also, a big note about the "jellies" name - now that I've listened to more of that video in the proper context, it seems Stealth was just communicating via text rather than actually speaking in the actual chat, so it's unclear if his answer was read aloud or not. I should also note that they seemed to be joking about Badnik names while they were showing Hidden Palace, so since you can't tell that easily then maybe the article title should revert. The only way to make sure this was his actual response is to ask someone who participated in the live stream, but Retro members seem to keep to their own wiki. LinkTheLefty (talk) 20:47, December 15, 2013 (UTC)
Renaming the article to "Unnamed Jellyfish Badnik"
I think that keeping the article named as "Jellies" is a bit odd- None of the staff who worked on Sonic 2 (2013) have confirmed that it is its actual name, and Nor has Sega. Should we rename it?
SnufflesTheDog, proud creator of Flying Garden and master of Sonic 2 and 3! (talk) 05:30, June 17, 2017 (UTC)