Behind us, have to draw fire away from Faye. Archer jumps up, spinning in midair to get a good look at the gunmen. Two tracking me, good. Not good enough. "Protect yourself!" Before he lands, Archer's sword is drawn: a plain, whitish shortsword, all hard edges and flat surfaces. He lands low to the ground, sword-arm outstretched, legs and off-hand bundled beneath him. A sprinter's stance. Have to make this clean. A splinter of a second later, he dives forwards again, directly past the middle gunman this time, the one still aiming at Faye. A flash, not quite of steel, and the outstretched arm is severed at the elbow. The pistol and hand drop with a thud, still together. ¡Dios mío! The other two followed through all that? At least Faye would be ready this time.
Disable the pistol-wielder and buy time for Faye to act without being shot. ((I don't remember if I have to spend Prana to attack with a Noble Phantasm weapon...))
@Anyone who looked at the sword with the note: I noticed the description was wrong when I checked to see which one I still had. The sword is not bland and mostly featureless, but an almost cast-iron looking black longsword, scarred with dull brown and orange rust. Because someone looked closely, they also notice the rust forms stylized flames down the length of the blade, highly unusual if this weren't obviously a Noble Phantasm.