What should the Overlord change when adding a fifth hero in Descent: Journey Into the Dark, 2nd Ed.?
We've been playing with six players (5 heroes + overlord). The only changes we've made are to:


Play all white minion monsters with red stats. They still count as white minions for hero powers. 
Add an additional treasure. 
When calculating the boss monster's HP, increase it by one hero. 


I think it's a little bit easy for the heros, but it's been close.