Okay so after playing Final Fantasy XII for awhile, I decided to get back into Tactics. Now I'm trying to get 100% pretty much everything. But what the hell is the Deep Dungeon? Is it the NOGIAS part? Also how do your acquire Ramza's Ultima spell? Need tons of help thanks. . .

The Deep Dungeon is like, the extra dungeon, it has dark levels (as in you cant see) where you have to go to a certain place (the location of the place is random, but there are only 4 or 5 possible locations for the exit) and there are, I think 10, levels of it, at the bottom, you get into a secret Zodiac fight, I only got to level four or five, so I have not completed it myself, but thats what I know about it.

Used crystals to light up the dark places, all the time. Easy!
But the last level of the dungeon you fight a monster, and that monster has a summon you must learn.

As for Ultima, you have to have Celia or Lede use it on you.
Coming from someone who didn't quite master, but did a good chunk. (There were a LOOOOT of items I didn't get.)

You also need move/finditem to go deeper into the dungeon. Rafta makes a good choice with it, because her faith is good, and her brave is low, so I think it aids in finding items (Hence, it being a chemist skill). Your summoner needs to get hit by Zodiak and survive to learn it, but it has a low chance of learning :/ But it's well worth it.

Same with your hero against those 2 assassin women.

If your going to acquire all the items in Deep Dungeon then I suggest getting yourself a guide unless you want everyone to have move-find item and check every square of the map of every level.

As what everyone already mentioned, Elidibs in the 10th level of Deep Dungeon where you can learn the last summon spell Zodiac and get the 13th zodiac stone or something.

It changes every time So I don't think a guide would help. But, make sure you don't kill all the monsters in the area before finding the exit, if you do, you'll have to start that section over.

Nuh uh because if it did then the Deep Dungeon guide at gamefaqs would be useless and also thats how I managed to accomplish Deep Dungeon myself so I think it would greatly help.

Yeah, of what I did of the Deep Dungeon (3 or 4 levels of it), I used a guide on gamefaqs, in fact I think I might go and finish that sometime withing the next few days now.