Spider wand

The Spider Wand appears in the episode "Dungeon Train" when Finn loots it from an unknown type of Boss Fight. The Spider Wand is a black, wand-like handle with a representation of a black spider at the end. The Spider Wand has the ability to shoot sticky webs and re-collect them, seen when Finn uses it on Jake.

Background
It is unknown where the Spider Wand came from, but it was probably generated by the Dungeon Train. It's current whereabouts are unknown, depending on if Finn kept the Spider Wand or if he left it at the Dungeon Train.

Trivia

 * Although Jake has magical stretchy powers, he was unable to move while ensnared in it's silk. This means that either Jake didn't think of using his powers or it can restrict magical abilities.