Lerks with adrenaline, or "vent lerks", are devestating. Not only do they spore you to death, and cover the entire room in the spores, they take your attention as well.

I've sat in the vent at West Core on lost so much as a lerk that I probably could build a nest there and claim it as my own. Adrenaline lerks are MUCH more effecient, I believe, than celerity lerks. Sure, they die easier, but a marine can survive a chomp attack, where he can't survive the wall of spores pushing him further and further away from his target.

As shown in caged, gorge's can be, oddly enough, effecient with spit, if concentrated on one target. I've seen two gorges spit down 3 seiges in shipping tunnels in under 2 minutes. Sure, that's quite a bit of time, but it gets the job done.

Ignoring aliens can go both ways. If you ignore that skulk in the vent, and move on, he can come out and hit all the nodes behind you. On the other hand, if you spend 5 minutes on trying to kill that skulk, you've wasted your team's resources.

-Mom