Games that have taken an age to 100%

[NinjaOnXTC]

I'm guessing GoW3 will fit in here nicely, according to some websites I've read on the achievement list.
Life.
FF #
Pokemon - color
Call of Duty (game, not achievement list)
NFS:MW (For when you're 12 and can't race)
Skyrim
Oblivion
Sid Meier's Pirates!
Battlefield: Bad Company 2

 

[TyrantGanado]

I remember being determined to get 100% on Just Cause 2. I think I got to about 79.69% and gave up since I had the platinum trophy. I did all the interesting bits, it's just crates and settlements left.

 

[NinjaOnXTC]

How did I forgot Just Cause 2...
I put ~100 hours into that game, and just thought "fuckthatshit.jpg"

 

[JesterRaiin]

Baldur's Gate : Big Picture.
It's a fan made modification merging each and every part of trilogy with some of biggest mods available. Some 200-250 hours of play weren't enough for me to finish even first part of this monster.

 

[NinjaOnXTC]

I'll make sure not to look into that, doing IB currently.

 

[LordLundar]

Spiderman 2. The worst part was the reward: NOTHING!

I can think of a worse one. Xenosaga Episode 2. Why?

To get 100% you must do everything, absolutely EVERYTHING and beat the final boss multiple times (7 if I recall correctly) to do it (the last thing you can do is pay an obscene amount to someone and the fastest way to do it legitimately requires getting an item from the end boss and selling it.

Your reward is a special attack for Kos-Mos that you cannot take into a new game, so the only thing it's good for is attacking the end boss with that you beat 8 ways to Sunday already. What a waste...

 

[StealthyNinja]

Crackdown. Those damn orbs.
GTA 4 as well as, getting friendships to high level is not nearly as fun as abandoning them in helicopters.

 

[The Unworthy Gentleman]

Assassin's Creed II on the xbox, I've got 100% on the playstation but for some reason cannot "sweep five guards at once" on the xbox!

Brotherhood is worse. I can't, for the life of me, get 100% synchronization. That damn tank memory simply is not possible to go through without attaining some damage at some point. The worst part is that if you take damage then you have to go straight back to the start to get it.

Then there are the multiplayer achievements. Honestly, fuck that.

 

[OrokuSaki]

Games that I have 100% completed are really only Kingdom Hearts 1 and 2. I did for Sly Cooper, but that was easy. But I've seen a game that 100% completion is not only challenging, its insane. And that's Disgaea. Any of them. At first I thought, oh hey, there's only _ levels, this'll be fun. Then I saw item world and thought "Ok, that's kinda repetitive", then I saw the class system. That is when I gave up all hope. In order to get the highest class: the Majin, you have to get one male Warrior, Brawler, Ninja, Rogue, and Scout to level 200+. In order to get ninja you must get 1 male fighter and 1 male warrior to level 10+ each. To get scout you must get 2 fighters/warriors to level 5+ each. And if you want a female majin you have to do the whole thing over with girl characters.

 

[Rad Party God]

Hmm... It never takes me a lot of time to complete a game 100% when I want to, normally I shoot for 100% at the second or third playthrough, sometimes with a guide on hand (or on-screen).

Last game I finished 100% was Arkham Asylum and I enjoyed every second of it, but admitedly, I used a guide for 100% completition.
It took me a couple of days to do so, less than a week.

Or... maybe the only game that took me a while to get 100% was Super Mario 64 and those damned 100 coins for every single level, it was a nightmare to get them all from the Rainbow stage.

 

[NinjaDeathSlap]

Assassin's Creed II on the xbox, I've got 100% on the playstation but for some reason cannot "sweep five guards at once" on the xbox!

When you find out how, let me know. Literally the only thing I have left to do in that game. Finding all the feather s left me traumatized.

I assume you've done the training outside Marrio's villa, then the best place to do this is outside the Doge's palace in Venice. Kill a guard to get a pike then make sure you havn't got a guard selected (left bumper) then press and hold B when the guards surround you, trust me you'll get there eventually!

And yes, the feathers had me in tears!

I think I misread your original post. I have in fact done the 'sweep 4 guards with a long weapon' achievement. The one I've still got to do is 'Stun 5 guards at once by throwing sand in their face'. I can never seem to get more than 4 at once.

 

[RemuValtrez]

Well the First Fire Emblem to be released in the west, the one one for the Game Boy Advance, took me 10 fuckin' years to just complete the base campaign. I've spent the last 5 trying to complete the Hard Campaign, and went that's done I've got the Hector Campaign to complete..... then the Hector Campaign to complete on Hard.

Yeah.... to quote a doomed polar explorer "I may be some time."

I know what you mean. It took me a long time to even beat the base campaign due to the last fight (which is split into 2 fights) was just a pain in my ass. Generally lost all my good characters (only a few were superpowered) in the first section as they would have to take everything on while protecting the rest. And then I'd be stuck with weaker main characters to finish it off. Took a yearlong break playing other games before I came back to it and powered up all the main characters and my favorite few. Ugh.

 

[KingHodor]

Probably Final Fantasy X.

Note that this was the PAL version which had the same features as the Japanese "International" re-release, including a new uber-boss called "Penance" ("Der Richter" in the original) that takes around ~75 minutes to beat because you have to keep destroying his respawning arms or he'll instantly wipe out your party with a single attack.
Just how uber is this guy really? The main storyline boss of the game had a whopping 180,000 HP in total if you count both his forms. Richter had 12,000,000 for his main body and 500,000 each for the respawning arms, so I probably had to inflict more than 25,000,000 HP worth of damage for him to go down. Naturally, you'll need to maximize your characters' stats and obtain their ultimate weapons (and get both upgrades to unlock their full power, for which you'll have to beat a number of amazingly annoying and frustrating minigames) to even stand a chance.

So yeah, in the end, I logged more than 200 hours of game time on my save.
PS: Anyone who "beat" the guy using Zanmatou (random instant-kill attack by one of your summons) deserves to have their game confiscated