Left 4dead 2= 320 hours
Team Fortress 2 = 325 hours
Im not entirely sure how I ended up spending that many hours in left 4 dead but with 14 campaign maps (including l4d1 maps) and about 45 minutes each that's 10 hours just to play through all the content. The thing is that turns to 300 hours from the variation, th AI director does such a good job of varying the game each time, you never really know what is going to be behind the next corner and the even greater wild factor is what king of human allies you'll have from pros to utter noobs. Then there was Versus Mode, that easily added another 100 hours for mixing things up further with any metric combat against an opponent you can fathom.
But I'm pretty much done with left 4 dead now, it's really just gotten to predictable but I've learned a lot about how to make a compelling game even when killing mainly AI opponents:
-have procedurally generated enemy placement, if you remember where they were just once then it loses all the excitement of trying to figure out where the enemy will come from
-allow full freedom in mission select and each mission about an hour long split into 10 minute sections with a mini climax for each then a big climax at the end of them all. Each mission is self contained and though in a particular order can be played out of order and still work.
-include a strategic element to combat, not just one guy standing and shooting but fields of fire and kiting bigger enemies
-include temporary power ups randomly placed. The laser sight functioned this way, making almost every weapon much more powerful but you could never depend on it.
I also really liked Left 4 dead 2's controls, the right click melee I love so much, it's an instant fus-ro-da that is great for close combat, stunning and pushing back. I'd love if call of duty adopted such a mechanic, replace the knife melee with a whack from the weapon stock to stun them like a stun grenade, then knife em or shoot them or keep smashing till they're kaput. Knife lunge is BS, but a BROAD swing of a club. Also great, swinging melee doesn't reset the reload of a weapon! I can't emphasise enough how such a subtle feature de-bullshits the flow of the game, and it makes sense; if reloading a weapon is. Series of steps then interruption shouldn't reset, if you remove the empty magazine then interrupt to punch then you shouldn't have to remove the mag AGAIN! So many games get this wrong, even TF2.
Right now I just want more games to be like left 4dead2 but what has really done it for me are the zombie opponents, even the fast runners are not enough of. Challenge ny more, they are just too predictable to run at you and claw at you. I do like the idea of hoards of unreasoning killers that are relatively weak and you have to mow them down in droves, but zombies have outlived their use.
Give me cyborgs, or vampires or something that might have more pack intelligence, some that are more likely to use the most primitive ranged weapons with setting ambushes and retreating. like the gandos in resident evil 4 but faster.
Right now I'm getting back into tf2, it has changed so much with all the many tweaks and maps, and I'm really getting into some of my less played classes like demoman and spy or just some of the weirder weapons of my familiar classes like the shortstop and FaN. I still am mastering rocket jumping and air blasting rockets, in a way I haven't "completed" TF2 yet, not to mention there are still new maps I haven't played yet with every class.
