Mysterious Stickman

Not just a "strange guy in a robe."
Ah! Finally, I did not think you would ever reach this point. Before you continue, I have been instructed to tell you this:
*States in a grand voice, as if reading from a script*

Twig the Moglin
First of his name
Devourer of Fish, Ice Cream, and Worlds
The best, most stick-iest designer Lore has ever known
Has prepared for you… THE ULTIMATE BOSS BATTLE

Next
*cough*
Alright. We're done here. My directions are to tell you to walk into the arcade machine. Yes, into the machine. Just… just do it.

- Quests

Location: Stick Quest

Thanks to Sammzy.