Balancing CR against unusually powerful groups

[Tsutsuku]

I've been running a campaign that kind of walks the thin line between gestalt and mythic - basically, in addition to giving my players a feat every odd level as usual, I'm also giving them a special ability, chosen by them and theoretically balanced by me, every even level. These abilities range anywhere from gaining a single basic class ability from another class (like mutagen or slow-progression sneak attack a la VMC) to allowing an aligned class with a similar prestige class (monk with Champion of Irori) and a few other odds and ends that are not as strong but full of flavor (a battle-oriented cleric using her fist as her holy symbol). A couple of players have also taken tier 1 mythic abilities for their choices.

The problem is that my players are now level 8 and they've been tearing through some CR 11 encounters like appetizers. Two of the players are min-maxers playing fairly optimized characters, and the other two are playing fairly average but still enjoying themselves. I also think that part of the problem is an NPC cleric one of them got through leadership that's been channeling healing during combat with a phylactery one of them crafted for him.

When I have managed to throw challenging encounters at them that actually feel like the right CR, its generally not because the monsters are actually tougher but because they've taken out one of the min-maxers and/or the cleric early on, but this usually results in near-tpk. I'd like some help figuring out a middle ground that's exciting for them and me, but doesn't almost kill everyone involved.

[zylphryx]

Unless the encounters you are throwing them against are also buffed in the same fashion as the PCs, you are not going to balance the encounters easily. This could mean throwing them against mythic opponents and building NPCs in the same fashion that PCs are built (extra abilities, etc), and similar tactics. Additionally, by allowing folks to take tier 1 mythic abilities, you really are not "walking the thin line" between gestalt and mythic, you are at best staggering along the line and stepping off into mythic.

All that said, since this is a home brew game, you could also bump up the monstrous ability effects. A creature has the grab ability? Have it add a significant bonus the creatures CMB and CMD for grapple checks. The creature has Awesome Blow? Allow it to be used on ALL attacks allowing the creature to knock multiple targets back in a round of combat and increase the distance knocked back by 5' for every 5 points they exceed the target's CMD.

Bottom line is the PCs are obviously not balanced if at level 8 they are blowing through what should be epic encounters. Unless you tweak the creatures they encounter in a fashion similar to what you are allowing for the PCs, you will not achieve balance and will have a very bored group of players once they hit level 12 and are easily defeating out of the book CR 20+ encounters.

EDIT: to be clear, the PCs' abilities could be balanced in regards to one another, but they are clearly not balanced in regards to the world in which they find themselves or the opponents they are fighting. It is a common issue when making custom changes as you described to PCs to neglect doing similar adjustments to the PCs' foes.

[Philo Pharynx]

Here's my ideas:

• Staggered encounters. Have more bad guys show up as reinforcements. Consider having them show up with buff spells from a caster or potion active. For example, if they've come from a ways off, haste would have helped them arrive in time. Staggered encounters help against people who have alpha strikes or who use mass debuffs against the enemy.
  One really nasty way to do this is to have them face fanatic opponents that fight to the death. After they die they become undead. They pretend to be dead until people search the bodies.
  
• Give monsters buffs. When you advance monsters normally, then it can get hard to balance because mostly what you have are hit dice or class levels. Giving them stuff outside of this can help. For example, when you have a monster that has good attack and damage, you can simply increase their hit points so they last a few more rounds.
  
• Get specialists. Are the heroes gaining reputation? Are they dealing with the minions of a powerful big bad guy? Expect that he has taken notice of what they can do and hired people who can deal with their common modus operandi. For example, if they have a badass archer, then Fickle Winds will shut that down. This one is hard to balance, because you don't want to make their choices invalid all the time, but you do want to make one-trick ponies realize that they need to broaden out.
  
• If they have an enemy, put the enemy on the offensive. Try assassination attempts in town (especially on the cohort). Get them separated. Attack their allies or hometowns. Even if this is a "normal" encounter, it will ratchet up the tension. It's also a good way yo pull them back on an offensive to allow the enemies to reinforce and rebuild.
  
• Plot-based xp. If you are giving them all sorts of extra power and then awarding XP as if they were an 8th level group facing a CR 11 encounter, this is crazy. Throw out the chart and give them levels at appropriate plot points.
  

[Gohaken]

Attack their wealth.

Have them lose stuff by dealing with a pack or three of well informed, divination prepared enemies that are very good at Disarm and Steal, and then D.Door / Teleporting.

They can drop clues and such to bait the PC's into chasing after them... right into a very well prepared ambush.
.

Another way to attack their wealth is to make it naturally their decision to use it on expendable things. That takes some storyline engineering -- in a high wealth game I'm running, I balance it some by making it obvious that if the PCs don't spend a substantial amount of wealth on their followers/armies, those followers/armies will lose in the mass combats.

So yes, they just scored 250K in wealth. But they need to spend 50% of it or more to revitalize their entire army's depleted resources, raise key followers, and otherwise equip them.
.

Last but not least, you can limit wealth power creep by limiting crafting. Crafting doubles magical wealth and triples mundane wealth, in general. Take away crafting time, or remove crafting feats like PFS does. It helps.

[zylphryx]

At this point I'm not sure how much of an impact attacking the PCs wealth would be. It will have an effect long term, but it would not have any impact in the immediate. And any long term effect would be based on how reliant they are on consumables compared to the extra abilities they have at their disposal.

[Tsutsuku]

We're already using plot-based experience. I do have an established group of three BBEGs working together - a necromancer with an undead army, a four-armed abberation pain taster, and a stalwart defender that's already proven to be a pain in the @$$. They're all in the level 15-18 range and have special abilities as well.

They've also accidentally become enemies with the cult of Rovagug, so either of those groups could jump in. The main group has data on their fighting styles (although two group members have died since then, so its only half-accurate).

In terms of the players' own combat abilities, I have a generally fire-based blaster wizard (burning skeletons have definitely started showing up a lot), a sort of cleric/paladin with rage that focuses on melee control and casting support, and a mouser/unchained rogue/vivisectionist who does surprisingly large amounts of damage as a tiny race. The fourth player died in our most recent session and I don't know what he's bringing in now.

The wizard is relatively straightforward to counter, but I'm not sure about the rogue-thing, who is the other min-max player.

[My Self]

Have enemies play smart. Players will hate it if you deliberately weaken them and make them poor and such. And you don't want to make the enemies too powerful. Smart enemies will force the players to play cautiously. Have enemies who Rambo around instead of showing up for a fair fight. Perhaps swap out feats the monsters don't use for feats they probably will use. If your party is getting ambushed by kobold crossbowmen, don't have the crossbowmen show up in broad daylight, pitch a tent 60 ft. away, sound a bugle, then line up and fire. Sting one of your players with a crossbow bolt from 360 feet out, in the middle of the night, when you're all around your campfire. Shoot your spellcasters while they're preparing their spells. If you have to fight a dragon, have the dragon swoop down, vital strike a guy, then use flyby attack to quickly get out of range. If the wizard flies in hot pursuit, have the dragon grapple the wizard and fly off with him.

Oh yeah, also be vague about the enemies. Add some confusion to what they're actually dealing with. Make weak enemies seem scarier, and stronger enemies less immediate and visible, so they mis-prioritize and perhaps use their better spells against weaker enemies.

If your party just burns through enemy HP, then maximize HP (treat d6 as 6 instead of 3.5, d10 as 10 instead of 5.5, etc.) and boost saves by 2 or so.