If this is the ultimate, I fear what the previous were.
This campaign has nothing interesting to put to the table. The lack of variety is enough to numb the brain; it's endless maps of walking from point A to point B through the same forest setting. Every map is a nonstop barrage of random progression-triggered horde events caused seemly at random. I was so numb that I genuinely got excited to see a gas can barricade in the penultimate map, as well as a slight change in setting (wow water!).

Maybe I wouldn't have such a bad time if the campaign wasn't filled to the brim with ai navigation bugs. The computer survivors get stuck on just about everything and sometimes just refuse to progress the map, forcing them to teleport to the safehouse. Not to mention how they refuse to pick up health packs outside the safehouse. It's not just them, the infected are an especially strange case, almost always spawning directly in front or behind the players. I had a particularly bad moment where three specials spawned on top of a bus directly in front of me not even a couple feet away. It really feels as if the director itself is confused.

I can't even rate this, there's nothing here worth rating. The most I see is a practice attempt at learning hammer and proving that someone can ship something.