Adventure Time Season 8 Episode 5 - I Am a Sword Episode Title:I Am a Sword.Episode Description:After Finn accidentally loses his Finn sword, it is stolen by Bandit Princess (voiced by Amy Sedaris) and used for evil. Finn and Jake pursue the thief, trailing her to both the Spikey Village and the Box Kingdom. It is here, in this last location, that Finn and Bandit Princess engage in a duel. While fighting, Finn's grass sword activates. With the grass sword, Finn accidentally pierces the hilt crystal of his Finn Sword, causing it to break. Finn becomes depressed, and Jake hangs up the broken Finn Sword above their fireplace. When the two are not looking, however, it begins to glow an eerie green color.