After a couple of days not playing I came back to Crysis 2 and I'm getting killed much quicker than I'm killing enemies... A LOT. Despite me having the drop on them, and hitting nearly every shot while the opponent misses a lot. Is it a return of damage modifier hacks?

No! your still sleeping, and this is all a dream. (X Files theme playing in background.)

if ur playing on US or EU servers then its the lag. He probaby killed u but the signal for killing u still didnt come back to u therefore it seems like hes one shoting u.

if ur playing on US or EU servers then its the lag. He probaby killed u but the signal for killing u still didnt come back to u therefore it seems like hes one shoting u.
Yeah lag can be annoying, but I was on Aus servers... maybe others were lagging? but it's been happening a lot in the last couple of days :/

Check if you gun barrel is bent. That's what they did in the old days, movies.