Mass Effect
[UPDATED WITH NEW MAPS] I recently posted about a glitch to become invincible on Firebase Condor, but I also discovered that it is theoretically possible to become invincible on any of.
I posted in another post about God Mode, where you can't die or be instakilled, but there are also maps that I like to refer to as Demi-God Mode -.

UPDATE: I have spent about 5M more credits since this post and have updated results - click here to see them! Ok, I promised to do a little experiment to.
9 October Update: The patch was supposed to fix the glitch, but it didn't. Click here to find out how to missile glitch after the patch/new DLC! I'll preface this.
From personal experience, I believe a Regular Spectre Pack wins, hands down! The only time you should even think about buying a Premium Spectre Pack (PSP) is if you've just.
This exploit no longer works after the last patch - you can still get up to the mountain, but you can't become invincible any more. Fun while it lasted! :).