The Armor of Zeldron makes its appearance in "Blood Under the Skin." It is kept in a cave guarded by Ghost Man. The armor grants its wearer the power of flight and protection from anything, even ghosts.
Finn sought the armor of Zeldron because Sir Slicer, along with other fully-armored characters, made him feel embarrassed about having a measly thimble for armor. When Finn wouldn't pay for Choose Goose's armor, Choose Goose gave him a poem instead, and Jake interpreted the poem for Finn to encounter the trials and obtain the armor. The armor seems to be embarrassment themed, given the nature of the trials and the ridiculousness of its appearance.
The Armor of Zeldron consists of a golden helmet shaped like a skull adorned with pink horns and two blonde braids that have bone-like ribbons attached to them. There are golden breastplates with large spaces for female breasts, and two white wings in the back. The armor seems to have been made to cover the whole torso of a large female with a similar physique to Muscle Princess. As such, it is way too big for Finn, leaving only his arms and legs exposed. However, Jake, using his Stretchy Powers, is able to fit into the armor as he wishes.
- The Armor of Zeldron was seen among the things being sucked up by the Lich's bag in Issue 2 of the Adventure Time comics.
- The name can be a reference to the Legend of Zelda series, a series of adventure-puzzle games similar to Adventure Time.
- In the original storyboard and prop design, the armor had swinging morning stars or skulls (as seen in the gallery below) attached to its nipples, but these were later scrapped because it could not make it past Standards & Practices, because they resembled a woman's breasts too much.