/rant ended
Zaodon explained to me the complete mechanics which I now understand. I just wish that the Stunning Blow feat would not break the attack cycle...
All stuff below this line is what I said prior before my rant so it won't be confusing for potential new readers.
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Really, REALLY?!
A fortitude save is required to stun an enemy for six seconds with no auto-crit. Sap is more useful here as it lasts for like three times longer and doesn't need a save. Granted sapped enemies break from the sap once they get hit, but with the tiny duration that stunning blow gives coupled with no auto-crit, what's the point?
I got one of my current characters with stunning blow on Lamannia to see if stunning blow was nerfed just like the caster's hold monster. I guess your main source of income is forcing people like me to buy Turbine Points so that I can get a feat swap to remove this now useless feat.
A caster can just switch in and out of their hold spells with ease, while it takes time and real money (Turbine Points if you're a level 20, because I am not spending two years to find and grind enough dragonshards to get a flawless gem) to swap feats.
...