Alright tyranid player here (Ork's and marines as well but details details.) anyhow I have a question that I honestly think is how it could work, but I wanted some second opinions. I fought a WAAC player a few weeks ago and he kept stating I couldn't do what I did because of rules in the main rule book blah blah blah.
Now onto my question which is: With the onslaught psychic power, can a tyranid unit run twice in the shooting phase?
Before you go all "Omg lol no u dumb kid" the psychic power states the following: "This is a psychic shooting attack that automatically hits a single friendly unit within 12". That unit may both run and shoot in the same shooting phase. The may do so even if subject to instinctive behavior- feed. A unit under the effects of onslaught may not assault unless it also has the fleet ability."
Now then my logic was that in the shooting phase I can run as per the power, and run again in place of making a shooting attack as per what the rules state in the main book. Now he argued that it was because of fleet or something completely unrelated, but I just desire to make sure that if I do this that I am not cheating (As I feel horrible if I forget a rule and get called a cheater.)
TL;DR can onslaught allow for a tyranid to run twice in the shooting phase?
Thank you.