Ax Bass

The family axe-bass is Marceline's family heirloom. It was originally a regular axe before Marceline turned it into a bass guitar. It makes its debut in "Henchman," where Marceline plays and sings the Fisherman Song for the Second Nut Son. Later, she orders Finn to kill the Dimple Plant Monster with it, but he refuses. In the episode "It Came from the Nightosphere," she plays the Fry Song with the bass. When Finn summons her father, he seems suprised that Marceline has it and takes it from her, asking if she's made it into some sort of lute.In her efforts to reclaim it, she is shown to care somewhat more for the bass than she does Finn, as she chooses to save it rather than Finn when the two were falling.

Design
It is an entirely red, double sided battle axe, which has two chips on the right side. The head stock was most likely added by Marceline, along with the machine heads, which are located two on each side. The pickups, also added by Marceline, appear to be single coils of unknown manufacture. The neck is fretless and the body has just two nobs, one for volume and one for tone.

Trivia

 * In "Henchman ", the sharp parts were silver. However, in "It Came from the Nightosphere ", they were red.
 * In "It Came From The Nightosphere" the Axe Bass is referred to as both a bass and a guitar.
 * Somehow the Axe Bass can be clearly heard in "It Came From The Nightosphere" when Marceline sings the "Fry Song " even though it isn't plugged into her amp. This strange phenomenon can also be observed in "Henchman" and "Go With Me ".
 * It is unknown if the Axe Bass has a truss rod, which curves the neck so that the strings won't lay flat against the fingerboard, although the neck must be curved somehow for Marceline to be able to play it.
 * It is one of three basses that Marceline owns, the other two being the bass in the episode Evicted! and the other being the Butterfly Bass in the episode Heat Signature.