Is A:CM the worst game ever to be released? No.
Is it completely devoid of possitive points? Nope.
Are these possitive points largely obscured by baffling plot decisions*, allies who managed to combine useless and obnoxious in new exciting ways, irritating scripts, sub standard graphics, downright broken enemy AI, and the nightmarish mess of an ad-campaign combined with awful after market support... and the fact the game will occasionally deleat all of your progress, with no possible way of backing up your save.
It was also horribly overhyped with an ad campaign which (initially at least) specifically targeted the hard-core fan base, but released with huge gapping inconsistencies which even the most cassual fan could point out.
And all of that is coming from someone who had the disk in his console for roughly 11months.
I played it.
I enjoyed it.
I think in some ways it is the closest we will ever get to an 'authentic' feeling Aliens game (in terms of basic aesthetic, sound and weapon feel).
... And that makes me rather sad.
Especially since the last decent Alien franchise game we got was AvP2... and that made some really questionable decissions with the graphics (the comic look, red shoulderpads, the odd skulls on the preds, etc).
A:CM is often made out to be, barely functional and the worst Alien game since AvP(2010), which was often made out to be barely functional and the worst Alien game up to that point. That's mostly hyperbole and nostalgia talking.
Both are flawed but fun in their own way. I think everyone should just look forward to sega loosing the liscence after Isolation.
*as in: "Who the hell chose to include that?"
