The easy way to deal with Great Marlboros is to have First Strike on Tidus, then have him use Provoke. This prevents it from ever using Bad Breath, and instead use either his spit against Tidus or a weaker version against the whole group. Just a note here: With this strategy, you cannot rotate Tidus out of battle. If you do, the effects of provoke wears off, and Bad Breath ensues. The key is: First Strike, Provoke, hastega, beat him down with spells or attacks.
Demonoliths are a different story. For the most part, I just recommend at low levels just having aeons take care of them, as they are immune to every status effect besides curse. It's possible to get armor in the Omega Ruins to help you deal with their counterattacks, which I believe inflict darkness, poison, and silence. Once you get stronger, you can develop actual player strategies for Demonoliths.
Let's go into the "archives" in "Washington D.C." and find out how people "masturbated" in the "roaring 20's."
Crao Porr Cock8. Bitch.
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