Short (Very Surface-Level) FFX Underleveled Guide

This is purely anecdotal, but I hope it may come in handy. I only unlocked Firaga until it nearly ended and I never had those fancy "special" abilites, "skills", or magic I saw people talking about in the forums. You may need to be strategic depending on the boss. If you want to do optional battles and areas that are stronger than the mandatory boss fights, this personally wasn't sustainable for me. For example, I couldn't fight a ton of monsters in the Omega Ruins, but I sometimes had a chance if it was a weaker one and I was not ambushed.


So, pretty early on, you can charge up each one of your aeons' and party members' Overdrives. Then summon every aeon in the list one by one, unleashing their Overdrive. If your opponent is not dead yet, you can unleash your party members' overdrives. Rikku has a very powerful overdrive, you can look up the list of stuff she can do.

Later on... you may feel like even this won't work! This calls for... Yojimbo! You can get enough money to recruit him naturally over time by fighting monsters in random encounters if you're early enough in the game. You can also sell some stuff. You can use a Yojimbo calculator (I found one online) to see how much money you need to spend to get him to use Zanmato.

Ambush protection! If you ever get ambushed and you know they will one shot you, get First Strike on Tidus, who can use Flee immediately.

I actually only got the ability to use this shortly before the last section of the game*, but you can use Rikku's Trio of 9999 on top of that if you encounter a boss that is still too hard.
TIP: In the boss battle before the last section of the game* Use Trio of 9999 or Zanmato (whichever you would prefer to use last) in the easy part that is intended to let you win, OR IT WILL TAKE SOOO LONG bc you're not strong enough.

Ok if you want to know, I finished the game using these tactics while being underleveled(with some strategization here and there), but your case may be different.

Here is me defeating Evrae T_T

Here is me defeating Wendigo
(The overdrives of the people in my party weren't necessary, but why not LOL)