I've got most Alien Swarm achievements under my belt. In fact I'm missing:
- SynTek residential speed run (time limit on a map)
- Nuke from orbit (kill 100,000 swarm)
- Outstanding execution (complete the entire campaign without anyone dying)
Nuke from orbit is basically easy (dunno if I'll even try though), and I'm sure the speed run can be done with some practice. I'm sure Outstanding execution would eventually come by just grinding, but seriously, that's a lot of work. But it's the achievement that I want most (after Hardcore, which I already got).
I think the main problem is stupid deaths. The friends that I'm playing with can handle themselves, same as I. We usually play hardcore friendly fire so we've learned not to kill each other (except the occasional panic), and we rarely play below hard onslaught at all. So the basic potential should exist, but I just don't think we'll manage a full campaign even on normal difficulty by playing the usual way. Yes, we've briefly tried on a couple of occasions.
What advice would you give?