I was playing a custom rumble match with my friends when I one shot my buddy with a 0 ammo sword left click. In the video you can see I did 276 and 56 damage with 0 ammo, only to be granted +1 ammo. I'm pretty sure 276 is the damage value of a normal sword swing, while 56 is the damage value of a sword hilt swing. No idea why I got +1 ammo, there's nothing funky going on here like arc empowerment. Something else to note - [i]before[/i] I swung at my buddy, he swears from his perspective, my sword already had ammo. The sword from the video is a Temptation's Hook with Honed Edge, Swordmaster's Guard, Tireless Blade, Whirlwind Blade, Impact Masterwork, and a Boss Spec. I have noticed strange behavior with a different Temptation's Hook that also has Tireless Blade. I'd have to dig through my clip folder to find a video of it, but I have occasionally been granted +1 ammo from just one right click kill. In my experience it should take two kills.