loves2spooge said:
Yup, the 7 Days achievement in Dead Rising is hard as hell (as are a lot of the achievements in that damn game), not only that, it nets a PALTRY 20G!
If you found that hard to beat, you're doing it wrong. Walkthroughs apparently abound on the web, but I got it on my first playthrough without a guide. The point is to not fight zombies - you're supposed to simply hide in a corner, reading a book IRL, and chomping down on a steak every few hours.
The hardest achievement I've seen is quite possibly I Am Bad Company in Battlefield: Bad Company. As someone mentioned earlier, that requires some truly ridiculous feats. Like getting 5 artillery kills in one round, repeatedly, or getting 20 headshots in one round.
Honourable Mention: Soul Calibur 4 has an achievement to get a single Soul Crush kill, and an achievement for getting 100. I have yet to perform a single Soul Crush, because it's a stupid move that you only ever set up against a stupid opponent as a way of mockingly showing how much you own them. The AI's never set themselves up for it, so you need to play online to get it.