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Copypaste from 
thread 1:
You're a former smith seeking for personal revenge. A former merchant full of lust for money and power. Whoever you are.
You just have left a village (or a city, according to Warband), and discover the open world around you, with several kingdoms, with some of them in a war with others (or not?)
You recruit people from other villages, complete tasks, punish looters. All for trust of kings and vassalship.
Or:
You punish looters, destroy villages (CRIMINAL SCUM) and wage war with that one castle.
It's up to you.
tl;dr you're a guy out for some reason and you eventually join a faction and kill enemies.
 - There's some secret stuff in the first game, samurai armour and a katana. I won't tell how to get them though.
 - Burning down villages is a good way of getting food and useless stuff that can be sold for a fortune.
 - The Sarranid Sultanate has a disadvantage in armor. That's sad because steel can cut through cloth if swung with a bit of force, unless the soldier is a mamluke. I've probably stated it in the first thread.
 - There's an exploit in every game that allows you to max your character the forget out.
 - Press R ingame for first person. Works in all three games.
 - In WFaS you cannot recruit from villages. Mercenary camps, on the other hand...