Mine is a game called two worlds. Its a cheap version of oblivion and it lags on single player!!! Its riddled with bugs and glitches. You find a glitch every 5 mins.
The worst game I have ever played,was Theme Park World on PS2.I couldn't understand the instructions,the graphics were very bad and you had to loose money to get money.It took me 1 hour to build one thing and took me 2 hours to work out the instructions.I played it once and then I gave it away.
It has to be Sniper: Ghost Warrior. The enemies can hear your silencer but not gunfire 30 feet away, and I have encountered times when I have thrown a knife at one of two guys talking to each other, and the one alive keeps on talking like he didn't see the guy bleed to death in front of him. The guns have an extremely slow rate of fire,have NO recoil, and take 4 hits to kill, not including the entire clip I have shot into people and the game didn't register it. The bullet drop isn't very realistic (it drops a tad too much) and when you shoot and kill somebody from afar, the people by the guy turn straight towards you position and, firing from the hip at 200,000,000 yards, hit almost every other shot. Blaghhhhh
It's gotta be Prey for the Xbox 360. if you haven't heard of it, i don't blame you. I played it for about 10 minutes. 10/10 of those minutes were a waste of time.