What are the mechanics for enemies retreating from combat?
Enemies can choose to retreat from combat for many reasons, both of mundane choice and special mechanics. One that can potentially come up often is the effect of the Craven ability of some adversaries:
Craven - If at the beginning of a round the creature is found without Hate points, it tries to flee the battlefield
There are rules for how a player character can retreat from combat. However, they make reference to the Attribute Level of the opponent, which is something only NPCs have. It also uses other terms that indicate that these rules are only for PCs trying to escape from NPCs (emphasis mine):
A companion fighting in close combat stance may attempt to escape when his turn to act comes. At the end of the round, a player-hero may attempt a roll of Athletics.
The TN for the roll is equal to 10 plus the highest Attribute level among the opponents that the character is facing.
Attribute levels work on a different scale than real, PC attributes, and do not seem compatible. As such, these rules for retreating do not seem to apply in the reverse scenario in which enemies are retreating from the players, in my opinion.
What are the actual rules for the retreat of opponents? Are they specified elsewhere in the book? Do they actually use the player rules with some particular interpretation or adjustment? Or are they something else?