Adventure Time Sword - Animated 3D Model

Just tried out Blender for the first time, I've never used any type of 3D programs before. I created Finn's original sword from Adventure Time. I think this is pretty good for my first attempt at using the program
It took a buttload of frustration and watching online tutorials though

However, I couldn't figure out how to loop the animation without it stalling or jumping at the end. Any suggestions would be greatly appreciated!

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