This is how to hack your gamecenter score and your achievements!
Sorry for long video if you are not that good with cydia u probably should watch. http://repo.insanelyi.com is the source for the score hack and overachiever is in big boss repo, which I'm sure everyone has.
If you can figure it out without video please like
For lethal center: play game, check gamecenter.
For overachiever: go to settings and turn on for any app that has achievements with gamecenter.