Luck is a stat in Mount&Blade and Warband. It basically plays the role of the player aging and becoming less capable as a warrior in their prime.
At the beginning of a new game, Luck is set to 200 and ticks down by 1 every 180 hours (7.5 days). There is no way to restore Luck or change the rate.
Luck determines the chance of a player receiving a permanent injury in battle, which will inflict a penalty to their attributes. Every time the player is defeated in battle, the game will generate a random number between 0-100. If the random number is higher than their current Luck, they will receive a permanent injury.
It is important to note that the random number is generated only when the player suffers a defeat which reduces them to 5 hp or less (the "wounded" hp threshold, found in 'module.ini'): therefore, the First Aid skill becomes crucial in the late game in order to avoid suffering permanent injuries.
Since the maximum randomized number is 100 and Luck starts at 200, a player will never receive a permanent injury until after 757 days have passed.
When a player considers retiring, they will be informed of how long they have played and their remaining Luck.
Effect of losing a point for each different attribute[]
Not every attribute point loss has the same impact on the player character. When an attribute point is lost, it does not merely translate into a "visual" number change: in fact, it imitates the effects of a level up, however reversed.
Losing Strength:
Losing Agility:
Losing Charisma:
Losing Intelligence: Intelligence loss may have the most devastating impact on the long term, because when the player loses 1 Intelligence, they also lose a skill point. If they have 0, they go to -1 (and then to -2, -3 and so on), with a + appearing next to their name in the party screen. Negative skill points can not be spent, therefore the player's skills are safe from harm, however this may easily lead to a situation where the player is pushed into a spiral, where leveling up intelligence is the fastest way to counter negative skill points, but leads into a trade-off with increasing other important attributes (e.g. Charisma to increase Leadership and Party Size)