It has the same design as the skinny sword.
The Glitch Sword is a weapon that is in the Weapons Frog, but is only available with the Level 256. To obtain this sword, you have to have a profile with Level 256 on it, and go into the Weapons Frog. Make your way into the back of the frog, and go past the last group of weapons. Right after the end, there is an arch between the inside of the mouth. Go to it and press X, and then you will obtain a sword that looks exactly like the Skinny Sword. However, when you pick up a new weapon in the middle of a level, the sword will cycle through all of the available weapons in the game. To get the weapon now you need a cheat engine/mods/hacks. It has the highest stats among all other weapons, although it's still not legitimate.