Return of Reckoning

Dont forget, when your hiding behind a wall in fort, no line of sight to any enemy and the nearest door is about 40ft away
constantly being hit by Rain of fire and phosphorous shells ----- Mysterious

I got knock down by Reprisal and immediately got punted off a cliff.
Arnt we suppose to have an immunity after a knock down for several seconds?

Does the tactic "Growing Instability" works when im using monstrosity path?
"Growing instability" tactic is under brutality path.