"Postgame" content - what should I be doing now?

I know there isn't really a postgame in this game, but I have a save file right before the last boss. I Just finished 10 of every monster in the arena, and I have every celestial weapon except for Wakka's Sigil. I have the actual weapon and the crest but I just need the final upgrade. So now, I'm wondering where I should be focusing. I know that leveling up sphere grids is a priority, but I mean I already visited everywhere and the leveling doesn't seem to get any better than Omega Ruins. I am super underleved for any of the creatures in the Monster Arena.

My highest hitting character is Kimahri (actually he has the highest stats of all my characters) at around 90,000 per regular hit, obviously 99,999 by criticals. But with HP being stuck at 9999 I die in pretty much one hit from everything in the Monster Arena and I just have no idea how it's even possible to level up at the speed Omega Ruins offers when you're at my stage of the sphere grid.

You should set your team up for the Don Tonberry leveling method outlined here. It's way faster than Omega Ruins.

Other than that, all you have left is pretty much just filling out the Sphere Grid, the Monster Arena and the Dark Aeons. You also may want to prioritize Wakka's sigil, since his Attack Reels overdrive (w/ his celestial weapon) will help you a lot when farming Fortune/Luck Spheres.

Kill the Dark Aeons and the other optional bosses. Penance! :O

I would work on Wakka's Sigil while also trying to set up some decent armor. Getting Break HP Limit will help greatly with the Monster Arena. Don't waste your time leveling against normal enemies. Get yourself Auto-Phoenix on some armor and start doing the Don Tonberry method of leveling. Even if you don't have Triple AP or Triple Overdrive for everyone, do a bit anyway. Double AP and Overdrive can get you pretty far if you focus on 2 or 3 characters.

Awesome thanks! I now have something else to do in Spira :)

I think all the stuff you do right before the final boss might be one of my favorite things about final fantasy games, I don't always finish everything and I usually have to use guides at that point, but I just really like that part of these games for some reason. Its even better now that we have the extra bosses and stuff.

Another question - I finished filling in the shere grid and have 2 characters that have completely filled it out (Tidus and Kimahri). Yuna and Wakka are very close but I need to grind Fortune Spheres for them now (man i hate that only 2 of them drop at once...)

My stats are obviously maxed ecept for Luck, which is 111 for both Kimahri and Tidus. I tested it out with Kimahri vs. Dark Bahamut and he was hitting every time, back when he was the only one who had the board fully filled. Do you think that'd be good enough for Penance? I heard that the Magus sisters are a bit annoying in terms of their luck but that they can be taken out with doublecast and Ultima, and you can separate them or something. Current goal is Dark Bahamut; Valefor, Ifrit, Ixion, and Shiva were all taken out with great ease. Actually, Ixion couldn't even touch Tidus and Kimahri.

Yeah I'm totally with you. My favorite part of Final Fantasy XIII's combat was the post game stuff because they introduced some massive, tough enemies that you needed the utmost precision and planning to take out. I still haven't done XIII-2's postgame stuff, it's on my list to complete.

I grinded by killing cactuars in the desert in the valley of castuars got 2-4 sphere levels per cactuar. Then I did it in the monster arena. I did the don toonberry thing just with one character because you need a weapon with triple AP, overdrive to AP and triple overdrive for it to be effective and most of my weapons did not have the triple overdrive part. For what to do, the obvious thing is to look at the trophies. I finally got platinum in FFX last weekend after 110 hours of play. Been playing X-2 a bit but I messed up the 100% completition despite following a guide so I would have to play again...and I tried the Last Mission thing and I didn't like how it played at all so those trophies will be a pain. I was so exited to have a 80 floor tall tower to fight in but then they changed the gameplay completely and made it into a grid based thing that is nothing at all like the regular game =(

I have not played anything like the Last Mission before, it seems so strange, you attack sort of in real time but you walk around on grids like it is a strategy RPG but it plays nothing like FF Tactics. It is in no way like Tartarus Tower in Persona 3 which I was expecting to be like.

@dagas: I actually have 125 hours in and I JUST got the Nemesis trophy. I did a lot of grinding for the Triple Overdrive, Triple AP and Overdrive - AP weapons. Not only that but I'm slow as hell when I play RPGs... lol. All I have left to do is kill Darks Bahamut, Anima, Magus and Penance, then work on filling in the sphere grid for everyone. I'm not maxing my luck because fuck fighting Earth Eater a MINIMUM 220 times.

Do you remember what your Luck was like when you took on Penance?

I had superbly overpowered party members by the end of FFX but I just used Zanmato to wipe out every optional boss that I would have otherwise not been able to by traditional means. It made the endgame stuff pretty easy. It would only take 3-4 tries per boss to get it spending approx. $55k each time.

@xyzygy: Don't bother maxing luck, what you're at is fine if all your other stats are maxed. I'm with you, grinding Fortune Spheres sucks. Getting your HP as high as possible is helpful for Penance but not required. The rest of the Dark Aeons are easy though, just be sure to use Auto-Life with Anima, she has an attack that will instantly kill you. The Magus Sisters are easy as long as you don't fight them all at once, in which case they are basically invincible. There's a little "game" which determines how many you fight at once. You'll understand when you get there, it isn't hard at all.