In the inventory, the Jellyfish Juice appears to be in a glass bottle with a light brown cap sealing it at the top. The juice itself seems blue-purple with bubbles in it in the remastered sprite.
The Jellyfish Juice's collection is only possible after examining the fireplace in Chako's house, since it requires the player to kill the queen jelly Kurara. Upon interacting with the fireplace, Chako will approach Quote and tell him that in order to pass through her fireplace, Jellyfish Juice from the jellies is needed.
Once the jellies appear, Quote can make his way back to the area where Santa's Key was found. The queen jelly should be seen at the top of the zone, resting on the ceiling. Shooting at the jelly causes her to become mobile. After sustaining 50 HP of damage, the jelly dies and a chest drops to the ground. Opening it gives the player the Jellyfish Juice.
Players are only allowed to carry one (two in the Switch Version) bottle of Jellyfish Juice at a time. After it is used, they can collect another by killing Kurara again. The Jellyfish Juice can be collected an infinite number of times, so long as the player does not already have one.
The Jellyfish Juice's use is prompted whenever the player examines a fireplace while the item is in their inventory. By selecting "Yes", the fireplace is immediately quenched, and any action associated with the fireplace occurs. The fireplace is re-lit when Quote reenters the place.
The three lit fireplaces in Cave Story can be put out to obtain certain items or transition to different parts of a location.
- A fireplace in Santa's House allows Quote to pick up the Charcoal, an ingredient for making a bomb.
- The fireplace in Chako's home can be put out to allow Quote to enter into the deeper part of the Bushlands.
- There is a fireplace in the Assembly Hall of Mimiga Village that, upon extinguishing, allows the player to receive the Bubbline.
- In the NiCALiS translation, Jellyfish Juice is referred to as "Jellyfish Jelly" in the inventory.
|General||Bushlands • Balfrog • Fan|
|Characters||Cthulhu • Santa • Chako • Malco • Kazuma Sakamoto • Professor Booster|
|Enemies||Power Critter • Jelly • Kurara • Press • Mannan • Frog • Petit|
|Items/Weaponry||Santa's Key • Fireball • Jellyfish Juice • Rusty Key • Gum Key • Charcoal • Gum Base • Bomb|
|Weapons||Polar Star • Missile Launcher • Fireball • Bubbline • Machine Gun • Blade • Snake • Super Missile Launcher • Spur • Nemesis|
|Items||Map System • Silver Locket • Arthur's Key • ID Card • Santa's Key • Chako's Rouge • Jellyfish Juice • Charcoal • Rusty Key • Gum Key • Gum Base • Bomb • Curly's Panties • Puppies • Life Pot • Turbocharge • Clinic Key • Arms Barrier • Cure-All • Booster (v0.8 • v2.0) • Tow Rope • Curly's Air Tank • Medals (Alien Medal • Medal of the Red Ogre) • Whimsical Star • 290 Counter • Teleporter Room Key • Sue's Letter • Mimiga Mask • Sprinklers • Controller • Mushroom Badge • Ma Pignon • Little Man • Iron Bond • Beast Fang • Prinny Cap|