[quote=@CAS1006]
[@Genni]They showed off real gameplay, it looks great. 
[/quote]
The same thing was done with [i]Colonial Marines[/i], but when it can time for the actual release of the game the quality had been cut back considerably so they could simplify the game engine to deal with the hoards of aliens required for the game.

They then cut back on the 'swarm logic' coding that they'd tried developing to make the aliens coordinate their attacks and act as a single enemy, since they couldn't manage to have the logic work flexibly enough to react to player actions, making the swarm end up losing control and just wandering around aimlessly as people shot them apart. For the released version of the game they stripped the logic out and just went for basic scripted sequences instead, losing the main selling point of the game.

Luckily the work on the adaptive logic design was folded into [i]Isolation[/i] instead, giving the Alien in that game a far better, and more menacing feel than a simple scripted nemesis could.