Probably 'To Live Forever' in No Man's Sky. Once you get to a certain point, it's almost impossible to die to normal circumstances, but up until that point random crap would kill you pretty easy. Also bugs. Especially with the Space Anomaly.
I ended up doing the 3 hardest achievements all at once in that game. (After double checking it was just the 2 permadeath and survival ones I did together but ended up using my permadeath save to do the "The Sentinel" achievement.)
Also, if you plan to do this this achievement. It's the easiest to just do the main storyline.