Me and my friend were playing Challenge Tower on his PS3, and after completing Challenge 96 (Test your might) the game locked up. Every time we complete the challenge it locks up, we've skipped the challenge but then 97 locks up upon loading. The prior challenges still work though.
The weirdest thing is that we've tried two different discs in his PS3 and the exact same thing happens, surely that's not normal?
We've tried Google but to no luck, thus \I turn to the Giant Bomb community. Any ideas? Has this happened to anyone else?
Thanks a lot.

I've had no lock ups on my copy yet and I'm at around Challenge 134 or so.

I have done all the challenges with no lock ups on the 360. I skipped 269, 275 and 300 so still have to finish those, I have no clue why it is locking for you dude.

Mortal Kombat does happen to freeze at all parts of the game, but not sure if its a disc problem or hardware problem... I frozen at start where the WB logo appears, but only twice so far for ps3

haven't had any freezes yet myself

Ive beaten the Challenge tower on ps3 and no particular challenge locked up, but the game has locked up once, i can't remember what i was doing but i restarted and it worked fine.

i get a sound glitch sometimes when mileena comes in on challenge 300 let us... let us... let us dance
i think a solution might be uninstalling the data the game installs even though it never tells you its there

I just completed a challenge on 360 and it froze. When I loaded the game back up, my save was corrupted. Fun times.

Worst I've got is sound glitches. But I've never had my PS3 lock up. I've completed all challenge tower missions.

Yeah I think I have the same problem, kept freezing up at 149, so I brought back to GameStop with the Warrenty.  
Got the new disc but came up with the same problem so I skipped that challenge, but now when I even try going back into the challenge tower menu it doesn't even load to that. 
I tried it on a new account, new save file and it works. What happen. How did my save file glitch and how do I fix this.