Only real biblical gaming session I've done was for 3 days straight. My wife had to leave town for the 3 days, so I played from when she left to when she came home. I was playing cod4, I vaguely remember dozing off once during that whole time. I was waiting for the match to load and then i woke up going what the hell just happened and i was sitting in the main screen. For those 3 days i pulled my bed up to the screen and did all other stuff between games.

Other than that i used to chronicly play 12-20+ hours straight.

longest FF10. most intense def jam fight for new york on hard in the story mode only.

epic UC2.

i remember WoW being brutal with 40 man raids. 5-6 Hours just wiping or clearing bwl/AQ40

Off hand the most intense was probably staying up till 5am playing Madden 11 with my friend. It was basically just one long ass game where we just kept doing special teams plays like fake field goal passes, fake punt passes, etc. It was fun as hell.

But of course I've had many long nights on CoD4, Fallout 3, and Oblivion.

I put 20 hours into MGS4 the day it came out.

Final Fantasy X probably played it for 14 hours straight before taking a break.

Longest, i think Pokemon Pearl has my record. Mostly because of the breeding and EV training. I never learned how to work with the RNG back then.

Intense, Espgaluda 2. I found very hard to 1cc this.

When I got COD4 (My first ever PS3 gameI bought) I played through the whole 5 hour campaign and then played about 4 hours of multiplayer.

When I first got BFBC2 Vietnam I played it for about 5 hours straight.

And Uncharted 2. Played through the whole campaign in one session, took 9 hours.

It's a little weird because I only really play video games for 1 or 2 hours at most nowadays. In the PS2 days I played countless games for 5 or 6 hours straight xD I miss being 9