I've tried to utilize Blade in the past but I find it to be unreliable with how I approach the game (I have trouble executing the extension drill attack).
@KikenEnryu oh the down down right where it really extends out? It seems to me like it did the most damage than the other weapons minus the flash of course. I loved extending out the blade into the bosses and watched the damaged parts almost instantly fly off them. Using it on the regular units was like a wand of instant death.