Defeating your players is hard, especially if you want to keep them alive.
I played a Shadowrun game once where I wanted to capture the players, which would bring them into the opponents base, where they could escape and work from within... only they refused to surrender, and pretty much were going to die to the last man before I just gave up and announced they were captured. And it wasn't like I didn't make it obvious they had no hope, I kept bringing in reinforcements and kept telling them it was hopeless... so why did this happen.
Well number one is a players sense of immortality. Players, and fictional heroes, are indoctrinated into the belief that they will overcome, survive, and triumph in the end, if only they can hold out long enough. This is an extremely hard expectation to bypass. You can help matters by telling your players that the game will be 'dark' or 'deadly' or 'gritty' or any other euphemism for character death, but that ultimately doesn't counter the 'heroic' nature of a player character in most role playing games. Nearly all rpg's are based on heroic fiction, the very appeal of this is the heroic nature of the characters. There are games around that don't replicate this idea,but for me I have no interest in them. Most of the time they are too close to real life in style for me to want to participate, real life is bad enough already. I play games for escapism, pure and simple.
So assuming your players have this predefined expectation, how do you get them to give up?
The simplest way, one which I have been using, is GM fiat...You are all captured, you wake up in prison. etc. Even then your players won't be happy, mine will rip off a list of precautions and standards tactics that make it impossible for them to be captured, alive, and spend a good 10 mins simply rejecting the idea. But at least no one dies.
There are different versions of this. You can get player buy-in to a capture, explain the premise of the story and how it starts that way, and get your players to agree. You can actually design the story around the concept that the only way they can proceed is to be captured, planting the seed and then allowing them to work it out, although this becomes very linear and obvious usually.
So what other ways are there? And while we are thinking about player surrender, what about npc surrender, how do you convince players to take prisoners? My players have no problem 'eliminating' prisoners who they can't reasonably dispose of, especially if the adventure requires them to move ever forward.
In a recent Runequest game I had to explain the concept of 'ransom' to some of my players. IN RQ ransom is an honour bound tradition (for everyone except the truly chaotic evil folks), written into the description of the world story, supported by the Cults and Gods of the world. As incentive to use it, players are offered financial or material rewards, and a character who offers ransom is honour bound to obey the lores and traditions applicable.. and players don't have to worry about npc's suddenly stabbing them in the back. In that RQ game, once I had pointed out the option, things very suddenly changed, players started accepting offers of surrender rather than fighting to a death. In the immediately following scene they negotiated a deal rather than storm the barricades. It was a surprisingly refreshing change of play style.
Thinking back on it, as GM, half of the problem is my own. I too expect players to be heroes, but on occassion I find myself expecting my NPCs to be heroes also. I unconsciously start 'playing' the game and turning it into an 'us vs them' scenario, which finds me being reluctant to surrender also. When both sides are thinking that way then the situation quickly becomes a 100% casualty result, which is ridiculous.
People do NOT want to die, players and npcs want to live, but in a game we don't really have to worry about that. Morale and fear of death rarely enter into the game play, especially once 'monsters' enter the combat. Most monsters are essentially psychopathic suicidal nutters.
The experience I had with the RQ game above triggered me to think more about this, hence this post. It occurs to me that there must be ways to use 'defeat' and surrender as part of the gameplay, without it meaning failure... or even more to the point, what is wrong with player's failing? Is failure not a realistic outcome on occassion?
Apart from the 'ransom' tradition of RQ, there are shortcuts you can use as GM. This is already implied in the use of 'mooks' by some game systems. Not only do 'mooks' die quickly, they vanish quickly also... ie they fail their morale test and run away. This 'run away' thing however can be near impossible in some game systems... and players can be particularly persistent in tracking every single npc down. So one avenue is to use mooks more, and give them really low values, and have them vanish into thin air... you just have to get your players to buy into the system.
Thats a good start for NPCs. I need to think more about players... but I am pretty sure it will come down to offering them an incentive to surrender. Surrender has to be made attractive.