A Sea Lantern is a block in Minecraft: Story Mode that is used as a light source, similarly to Glowstone.
- In "The Last Place You Look", some sea lanterns can be seen when landing underwater in the Mob Grinder.
- In "A Block and a Hard Place", Soren and Jesse find a sea lantern inside Ivor's Cottage. Soren explains that it was originally crafted by The Order of the Stone using prismarine crystals and Prismarine Shards. Later, Jesse uses it to solve a puzzle deep inside Ivor's cottage.
- In "Access Denied", sea lanterns are used as the primary source of lighting inside Harper's Secret Laboratory. There is also a portal made out of sea lanterns in the Portal Hallway.
- In "Hero in Residence", Jesse uses a sea lantern to solve a puzzle in the Sea Temple.
- In "Giant Consequences", sea lanterns can be seen multiple times inside and outside Romeo's Icy Palace of Despair.
- The Order of The Stone once gave their only sea lantern to Ivor along with several other treasures to prevent him from revealing their secrets.
- The cover artwork for "A Journey's End?" features a portal made out of Sea Lanterns.
- In "Hero in Residence", if the player repeatedly crafts Prismarine instead of the intended block, Petra will angrily give them a sea lantern.