OK, can someone explain to me why Rusty's ac is stupidly good. (Not going to lie Rusty was cooking)

This is the first time of me actually using rusty's AC. And I have to say it's amazing. The ability to Dodge at the last minute.Do the ability to literally get at close rain and still cause damage is unimaginable. even if you get a certain distance, you still take damage. This is the most impressive AC ever encountered. This is my first time actually trying a light ac. I did not get staggered, not once when using this AC.