Alright, so,
AtomBoy, legitimate bug this time: Explosions caused by propane tanks and the like seem to count as damage done by the player.
Now, "Propane tanks?" some of you might be asking yourselves. Yes, it is the first time I run into them too. Interestingly, this is also the first time I'm involved in mass combat where everyone can suddenly turn hostile on you in case you do damage to them, and the map is full of fragile propane tanks that, should they explode at the wrong time, will turn your allies hostile against you. Good times.
Here's a save, for reference:
https://www80.zippyshare.com/v/7FdQ6Gc3/file.html
Notice how if one of the "Mutants" in front of the player character is killed, the other will throw a grenade and explode the cannisters, turning the "Fighters" hostile. Notice how there's no way to resolve this without cheats, because there's multiple mutants there with grenades, and if anyone is taken out, some other mutant will throw a grenade and turn everyone hostile.
I would categorize this bug as fairly severe, considering that there is absolutely no indication as to why everyone suddenly turns hostile, and it took me several loads before I realized what was going on, and also because this is both the only place so far where I've seen these kind of destructible propane canisters and the only place I've been that has had this kind of zero-control-of-the-situation mass combat.
And while not a bug, there is another oddity: When you choose which group is to attack "first" (although it seems everyone attacks pretty much at the same time anyway), the player character is teleported to that position (but it is never indicated that you will be leading whomever attacks first). But more importantly, should you choose to pick any other attack route other than the frontal assault, your team members will not be going with you, leading to them running straight into the base as part of the frontal assault while you're left in the back of whatever charge you partook in, which will inevitably lead to you not being able to meaningfull contribute to the battle, as well as almost guaranteeing that one or more party members die, since they all love shooting eachother up.
Edit: Also, party members do not seem to be "in combat" at the same time as the player. When they go "out of combat" (such as after killing the last opponent in their vicinity, at some distance from the player), they seem to disregard any orders given, and beeline straight for the player character, without any cost to AP or limitations otherwise, making it impossible to actually set anything up in this battle, rendering what abysmal CNPC controls exists literally unusable. This can be observed in
this save. Notice how the player character is in combat, but the CNPCs will still follow him real-time.