This is a pretty basic question but I can't find any detailed explanation. All I can find is about the stun strategy in Ifrit hard mode, which is very specific (stun eruption only or it will start resist it), so I always thought it's a special set up case for Ifrit.

I'm leveling my PLD and running some early dungeons. Yesterday I was doing Hakku Manor (lv28 dungeon). The final BOSS has 2 abilities with long casting time. One AOE and another with high damage. I was trying to interrupt them every time but find myself failing quite often lately.

Someone told me that stun only work 4 times on a mob like sleep, but I think in the Ifrit fight eruption happens more than that? (I only assume this because I never really count that lol).

Is there any general rules for stun that apply to all the mobs (bosses)?

Thanks.