[@TheHangedMan] different ones. it was the dagger. this one is a needle (a throwing knife). He carries strapped on his legs (He actally uses those to aid in healing too, stitching wounds, etc.) They are actually not that long, 5 or 6 cm at best.

Even if he knew about them, the surprise of having them pressing your ribs without you even seeing them should at least surprise you (not much, since you can regenerate, and it wouldnt be a fatal wound. but the poison would be annoying) 

Oh, and i'm just waiting for your answer on the current situation to get back from the restroom