You not only go in HOT and I do mean HOT people. HOT= "go in swinging because all hell has hit the fan as soon as you enter" First combat is insanely hard because the bad guys get insane initiatives which is OK but to have them have insane amount of mobs that do distractions and poisons to the party, plus the summoners having insane full round attacks, plus summoners having free attacks that affect the party when they move is a shredder, plus the43 swarms having . I was in a scenario where 4 of the 6 people died and we had to call the scenario off just from first combat. Party was mostly unable to move from the distractions, con dying from poisons while unable to move, massive health damage from the full round attacks of the bad guys type mobs, free damage from the several swarms, and messed up badly from their free radius affects just from each time they moved and being confused where you also can attack fellow party members didn't help the party either. It's a shredder no matter how you look at it. I was using my alchemist that could barely keep up before having to run after 4 party members went down and bosses were barely damaged in the first combat of the scenario.
I played it and not totally understanding the army mechanics didn't do well with my first army but by hearing how others played I learned and my second army did great. The enemy getting way more reinforcements then us hurt but not as much as the swarm of Tieflings. Not even bastion of good could affect their volley of arrows. I don't see how their making a person do a reflex to take half isn't considered an attack or how bastion of good doesn't help at all against their bolts. The army fight was only affected by charisma for initiatives and morale rolls but most of the affects came from having the boons on the list and which army you picked. The scenario kind of drags on and lasts I'd say about 6 hours. Don't get me wrong if you don't have much of the boons the army fights are hard and your party has a hard time getting the prestige from winning the army fights.