This idea is very young yet, and only has been chatted about.
The basic concept is when you start a guild war, you set the parameters for it. In the case of capture or kill, and the different meanings of kill, it is pre decided on. And in the case of ?fair play being implemented, a larger more powerful guild would have longer captivities.
In most cases captivity will be doing remedial amount of work for the opposing guild, not so much ransom?but money could be exchanged for less or no work.
The main thing is so that guild wars have another facet then who?s side can stay on with the most people the longest. Death or capture have consequences that will require a victor to emerge eventually.
The captors will not have total control of the ones captured, but the ones captured might have limited movement and in order to remove the ?captured status? may need to make it back to their guild house, thus making breakouts possible.
There are many ways to do this, but it will only be done if it can be fun, and enjoyable to some extent?.after all someone who seems captured, could actually be a spy for the other side waiting for a moment to sabotage something.
Slavery, and this are not the same. You will not be forced to do anything?though working will get you out sooner. Or dropping from your guild. Or bribes, or many other possibilities.
Slaves have no hope of release, here you are kept in penalty for an hour or 2 at the most, as long as you do the work?if not it would be longer, or in some cases, you become a none combatant afterwards?(can not be part of this guild war till it is over from this point on)
But many of these choices will be dependant on guild leader choices at setting the guildwar up.
If you logg off and wait for an hour?well if the war is still on, then he is still sitting there, if it is over and your side lost?he is probably there, unless some deal was reached as a peace settlement.
These are all just ideas at this point, but I like this better then the concept of slaves, Slaves in this game will only be summoned creatures and or pets?None of the playable races will be a slave, except to an NPC, and even then it is questionable.
The player will always have choices to get out of a situation they do not like, but the choices will have consequences.