Over the weekend I was playing the original XCOM computer game (not the 2012 one, the original from 1994)

On the tactical missions it is turn based, each trooper having so many TU (effectively action points). If a trooper doesn't use them all, and they have enough to make a shot, they might make a reaction shot on the Alien turn.

I am advancing. I have one trooper in a position to watch a possible line of advance, and another back a bit out of line of sight behind a wall - the wall is the side of a building, where the wall on one game square is destroyed (effectively a chess knight move - two grid squares back, with the gap in the middle, and one to the side). Because the game tracks every shot, rather than just hit/miss, it is possible for misses to hit something or someone else, hence keep them back a bit, so stray alien shots don't hit.

Alien Turn

Alien appears.

The trooper watching doesn't shoot (failed its reaction roll basically).

HOWEVER...

The trooper kept back, it turns out, CAN see the alien...

And reacts...

Hitting their comrade with their first shot in the back from 2-3 meters away...

Killing them...

The fact that shot 3 hit (and killed) the alien DOESN'T MAKE IT BETTER. This isn't soccer, where scoring to cancel your own goal takes the edge off. 

       

I loved X-Com
Terror From The Deep is even better. If I ever find it, I'll lend it you.

I found TFD a little too samey when I had the original.  Mind you, never actually completed the first one! Wish you could do just the battles.

Xenonaughts is a good update, but mine has a habit of shutting down.

This post is actually about Karma rebalancing.
Latest mission*

I needed to get into a warehouse. As seasoned players know, the best way is to, ahem, 'make' your own door (that is shoot a hole in the wall...)

Being a warehouse it had concrete wall, so I fired full auto (more AP, less accurate, but 3 shots, not 1)

First shot breached.  2nd went somewhere into the dark.

3rd hit the alien who happened to be on the other side of the breach (the game hides anyone or alien not in LoS of a trooper). I didn't know about the alien until AFTER it died.

Few turns layer wanted a hole in the wooden wall on the other side of the house I was in, so I could see through. Fired a single shot, as it was wood. Immediately revealed there was another alien by the gap!

That met a 2nd shot. Terminally.

*I did lose 3 out of 14 troops at a terror site but that was just gameplay, not helped by it being dark, about 3am local time