Finally pulled myself away from my seven-year-old recreated characters and previously-paywalled powersets to try the sentinel archetype for the first time, and something odd happened on my first outing.
I'd been reading that I shouldn't expect all that much from the Opportunity mechanic, but when my DP/Fire rolled out, the result was a nearly-uninterrupted arresting rampage all around Atlas and the Hollows. I'd thought they were supposed to be like semi-ranged Scrappers, but I was playing like a semi-ranged Brute, and chaining Opportunities into each other before the bar could drain. Hit level 6 before it even occurred to me something was off.
But once I hit level 8 (and the entire time I later played a Beam/Rad), the Opportunity bar would empty completely once the buff wore off and start building anew...which I gather is supposed to be how it works? For a brief, glorious period, my Opportunity bar was instead decaying like Fury, and as long as I was attacking, I could literally end one Opportunity and go immediately into another. Was this just some weird server glitch?
And if that's not how Opportunity usually works, well...could it?