Scaling up The Skinsaw Murders (minor spoilers)

[LogantheBard]

Hello all! I'm looking for advice on how to scale up the Skinsaw Murders for my current party.

When the party started out, we thought that we'd only have 3 players, so I let them do a high-powered roll (4d6, reroll ones) in an attempt to compensate for the shortage of players. Well those players brought friends, so now are party fluctuates between 5 and 6, all with the same (averaging 50ish point buy) inflated ability scores. Book one was pretty easy on most of them, even with my upscaling. I tried adding additional baddies, adding fighter levels to the existing baddies, even combining multiple groups of enemies together, and they're still doing pretty well at destroying everything.

I'm inexperienced in scaling up encounters, and am generally not tactically sound enough to determine what could best challenge the party. I'm not opposed to completely rewriting every fight they'll encounter, because I'm sure it's going to come to that.

My party is this (Level 5, was just confronted by Sheriff Hemlock about the murders at the lumber mill):

Gnome Sorcerer - Rakshasha bloodline, specializing as a fire blaster. He is the party's primary damage dealer.

Human Rogue - Chameleon Archetype, Going for Sleepless Detective. Took two-weapon fighting and weapon finesse as combat feats, with most of the rest of his resources going to increase his "Batman" skills, as we like to call them. With another melee character, a pet, and summons, he's always sneak attacking.

Half-Elf Druid - Animal Companion (Crawling Vine), specializing in summoning. She competes with the sorcerer for damage per round, and completely wrecks the action economy of most fights.

Half-Orc Paladin 2 / (Flowing) Monk 3 going for Champion of the Enlightened prestige class. He excels at being an encyclopedia and battlefield control. He has devoted feats to excel at this aiming for Combat Patrol and Ki Throw.

Half-Elf Ranger Crossbow Style, Skirmisher and Battle Scout archetypes. He's slow to develop, as crossbow rangers usually are, but has been a useful utility character to the party.

[Tangent101]

Holy smokes. You know, I allow 4d6 reroll 1s and averaged 25-32 points. Or did you not have them drop the lowest 6 and added all four dice together? oO

First... you could talk to the players and ask them if they can scale down their stats to a 30 point build. Anything over a 20 that wasn't scaled up naturally (through adding points to stats at level 4) are capped at 20... or better yet, 18 unless racially they're allowed a 20 (thus humans and half-humans would have one stat that maxes out at 21 potentially). If they agree to that, then you don't need to follow the rest of these suggestions.

Next, I've got a level 6 party running through Skinsaw Murders now - they're about to start it. I started them at level 2 so there wouldn't be widespread immediate deaths and have thus been turning lots of Goblins into Fighters instead of Warriors and the like to increase the CR rating by 1.

Do something similar with all the Ghouls and Ghasts. Add one or two levels of Fighter to each ghoul... and give them feats that improve their combat effectiveness. Multiattack is especially nasty as it will improve their chances of hitting with three attacks. In addition, the Advanced Creature build will improve the DC for their paralysis attack and their disease-causing talents.

Now, when they go into the Haunted mansion? Increase the DC for each Haunt by 2 or even more. I'm assuming that just about everyone in your group has a Wisdom with a minimum of 14?

Finally, play up the horror of the situation. And if you find you overdid things? Give them a chance. If you made things too tough then weaken the ghouls afterward so that one last blow kills the ghoul and they survive by the skin of their teeth, or the ghouls start fighting among themselves.