Twin Blade is a weapon available to use in the game. It's a fast weapon, good at 1 vs 1 combat and high accuracy. You can use magic with this weapon and Guard (using the blade(s)) as well.
Special Action Edit
Hold the Square button to make your character separate the weapon as a dual sword. Pressing and hold Square button will combine the sword back to normal. In this form, you'll do a infinite combo but each swing use your Pulse meter. So, watch out.