A solution for the dilemma of how people are going to choose whether or not to kill someone after a battle would be to put the chat box to use.
For instance, let's say that I am a rouge ninja on the run due to a bounty and two shinobi have caught me, cue fighting music. We fight and fight and fight, assuming I am strong, eventually I manage to I guess knock one of them out, or however you guys decide to go about doing that. Anyways, one of them is out of the fight, knocked out over by a tree. It is now a one v one, and I somehow manage to repeat the process and defeat the second opponent.
Now, if you guys some how can use the chat box to display a message saying something along the lines of "You have defeated <player> in combat, you have <number> minutes to decide what to do!", then below that give them some chat command to decide to let them live, or have two keys, 1 being live another being death. This way nothing will appear out of nowhere and inhibit you from fighting, and if you can you can easily push the button and decide. Granted, there is the possibility of mistakes, but then you have the chat command to compensate. The time limit also adds to the realism, because if you don't kill someone, and they aren't bleeding out or something along those lines, like if it is just a KO, they won't be out cold forever. Thus, if the victor forgets about someone, then they will be awoken on the same spot, but in a weakened state. Adding to that idea, if you are defeated in battle, your screen should go black or goto something else that way if you do manage to come-to, it'd be like you were knocked out in real life, you wouldn't know where everyone is or what's happened. Also lol, I just keep rambling, if possible to make it realistic, if you guys decide to add the knock out thing, if you come-to after the time limit has expired, your screen should be a little fuzzy or something. Meh, just some ideas and thoughts.
If you need anything clarified or have an questions, feel free to ask! ^^
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