The rulebook stated that the adversaries spawn at the marked spawn edge no closer than 8" or as far away as possible if they are forced to deploy closer than 8".
Yesterday i had a situation in a 2 room dungeon. Both heroes were in the treasure zone. One on the left the other on the right side. Two adversaries were also in this zone. I draw an event card with reinforcement 3 = 2 because small dungeon. The two frosttrolls spawn so to say in my face about 4" away. Every hero movement triggers at least two minion reaction. I was short to win but it was not possible i became overwhelmed.
Have i understand the spawning mechanic correct? I have the feeling that you can´t kill the minions fast enough because they spawn ride back in front of you especially in the smaller dungeons.