Quote Originally Posted by Zilon View Post
Another question. In dungeon, there is a bar that slowly fill up at the top left of the screen. I am not in the front of the game right now and I dont remember the name of it. I seem like something that build up and then you get something positive out of it. Can someone explain it to me?
I think you're thinking of the Limit Break guage, and yes, once it builds up you can get a massive skill from it. It's party-wide, so anyone from your party using a Limit Break will knock the gauge back down, so there needs to be some consideration to who uses their "Limit Break" action. Melee DPS get a massive single-target attack, and that's a common favorite for finishing off the final boss of a dungeon. Caster DPS classes get a big AoE attack that's good if a lot of adds join the boss. Healers and Bards get a big healing limit break that heals the whole party. Tanks get a limit break that significantly boosts everyone's defense for a while.

Here's a page that explains it in a bit more detail:
http://www.ffxivinfo.com/content/limit-breaks.php