Thank you for changing the combat system so late entries don't bring with them companions and more enemies. It was getting frustrating to be almost done with a battle, only to find myself surrounded by three new, fresh, enemies, and the play who brought them on the other side of the room, who can then wait for you to die, then claim all the treasure.
With the new system, however, how is treasure divided? It would not make sense for a player who waits until I have only one enemy left, come in and bring a single additional enemy which I help to eliminate, then get half of the treasure. It should be divided by the number of enemies you brought into the fight.
That is, if I start out facing five, and someone joins and brings in one, the treasure should be divided 5:1.