Symbol on mission select? Under "Exploration?"

[Claymorb]

I've been searching but I can't find what it means. I'm on mission 3, and when I look back on mission 1 and 2, it only highlights one, so I did ONE of them but I have no idea what it was that I completed. I completed the challenge missions, found all the elite guards and weapon modules stations but only one of the two circles + symbol in mission 2. Any idea?

[WeissRook]

Ahh. Those are weapon upgrade points. They fill up as you find the secret areas (the ? next to them). If you notice, each Mission has one as well. If I remember right, there's also 5 combat ones per level too.
Keep in mind secret areas usually have stuff in them, but the stuff in them may not be collectables, sometimes it's armor. Each classic Doom level I think counts as one after you enter it.

[Claymorb]

Ahhhhh. Now I see what you mean. Yeah I just got the 5 combat points to go along with that. I wondered why one was half-ful after finishing it before I read your post.

Appreciate it.