Proximity Mines were a big hit around here, too. The rule set we would use for that one is that we could shoot the mines with the guns, but not each other. Oh, and no planting mines on the Proximity Mine boxes either. The mines aren't as fun as the Remote Mines in Perfect Dark, hoo boy did I have fun with those. I loved planting them on people and then detonating them when they least expected it. When my friend and I played on a team against the simulants, I would toss a bunch of mines on him and send him out into the hoard of simulants, then detonate it when they were all close enough.
Anyways, getting back on topic, I thought of a couple more questions about this game (sorry I've been so inquisitive as of late!).
Would I have to play the campaign mode to unlock any features for multiplayer? Because I'm not so sure that I would want to play that portion of the game...
Has anyone encountered any glitches? It seems like every time I play The Conduit, I discover a new one. Just today, I saw someone who kept switching teams, somehow. Each time he did, his score would increase the overall score for the team he joined. The match ended with each side having over 400 points.