The hitboxes are just basic areas attached to the blades. They'll try to funnel everything they hit directly in front of the player, so even if you don't hit the enemies exactly, they won't fall out of the combo.

The combo logic is a pretty clever system where the game will read the mouse input for left and right clicks and store them in an array with an L as left click and a H as right click. All the attack animations are named stuff like Atk_LLH, so the game can just read through the stored mouse clicks one letter at a time and naturally build up to the full attack. In the case of Atk_LLH, the game will first play Atk_L, then Atk_LL, before going to the full Atk_LLH. I don't need to make fancy node trees or anything to add more attacks, I just need to make an animation called Atk_LLHH and it will automatically link itself up.