Troops wish to join you?

[Ryastar]

No, at the beginning of the game, the game just sometimes generates "friendly" stacks of monsters. There will be only one type of troop, and it will just wait to be accepted. I think that there is always a friendly stack of wolves in the werewolf area in greenwort, for example. So this is just a random thing, and has nothing to do with hero stats etc.