I intend to spend the next couple of hours with my eyes glued to a hammer compiler (internal groan). Lets see what I can come up with for Swarm Tactics on Diema. I reckon that I should be able to create 4 seperate spawns near the start that clash at the first hack objective. Unfortunately it means i'm also going to have to do a little displacement editing.
Hammer by itself isnt that capable at terrain generation (I usually use stuff like Terragen for that, 8 bit black and white heightmaps) so I'm probably going to need an hour or two to extend certain areas to add working spawns and even more importantly, propper pathmapping for the swarm so that it doesnt become like a certain l4d area I could mention.
