Blue blubber jellyfish are a type of jellyfish found to the north of the Deep Sea Fishing Hub. They act as a level 91 baitless fishing spot. Blue blubber jellyfish may be fished at to receive raw blue blubber jellyfish and 390 Fishing experience.
A blue blubber jellyfish may occasionally electrify itself, signified by its name changing and its model changing to depict it emitting particles. Fishing at an electrified jellyfish causes a debuff stack to accumulate with each catch. Non-electrified jellyfish spots will reduce the debuff by 2 stacks per catch. If the debuff reaches 10 stacks, continuing to fish at an electrified spot will cause players to be stunned for about 10 seconds upon a successful catch (this can be cleared with Freedom).
If a player is stunned by an electrified jellyfish, the debuff will transform into a 2 minute cooldown, which will refresh itself if the player is stunned again during that time. As a result, players will be unable to fish electrifying jellyfish without being constantly stunned, although they can continue to catch non-electrified jellyfish as normal. The debuff vanishes completely after the cooldown ends.