Agile activated on every attack

What you were expecting to happen, and what actually happened?
Completing challenge on Grosh-Nak. Fired off Sheggra spell. Every attack triggered Agile trait. Including Glade Warden’s magic spell.
What are the steps to make it happen again?
Have not re-attempted challenge but will update will more info.
Do you have any screenshots or video you want to share with us so we can see the problem? Attach them to your post!
No. Sorry. Hard to catch a multiple, repetative Agile dodge.

Just tried the same challenge in Grosh-Nak - Orc this Way - five more times with no repeat of glitch.