Making an encounter last longer

[roguemetal]

Introduction:


I have been DMing for around six years at this point, quite steadily too, and I've seen a constant influx of players who want to do nothing but more damage. My history and the draw of my sessions has always been strong character growth, original world concepts, and extremely memorable plot moments. Plot moments which no longer have a place in an encounter, since one turn should be more than enough for a group of players to take down an NPC of 3-4 levels higher than themselves.

I used to make encounters that would involve incredible environmental factors like the party plummeting to their death from the skies on the deceased body of a great wyrm while fending off a smaller dragon diving after, and a group of kobold also on the wyrm trying to ensure the party dies with them. Or fighting a giant turtle that is causing flooding in a port town, where the fight takes place atop rooftops that won't hold up. I hope these days of grandiose encounters aren't over.

Most of my games are between level 5-12, and I rarely restrict anything but equipment. That said, they still manage to get past DR or resistance easily, have few problems with saving throws (if one party member is incapable of action, they deal with it after the battle) and rarely do they specialize in taking a hit, making my plans for near-death circumstances hard to calculate. Essentially, these last two years I've seen a major shift to glass-cannon characters, and it's a problem.

So my question:
How do I make an encounter last longer?

Increase AC? Rogues are already missing 80% of the time.
Add SR? Casters are beating most SR by enough, and raising it much more just makes them use spells that don't target their opponents.
Raise CR? Higher CR means more experience, which may progress the game too quickly.
Increase Hit Points? This seems to work, but high Con isn't easy to come by, and high isn't always high enough.
Spells? Polymorph, Wall of Force, and other damage shields don't stand a chance to players that make use of dispel magic and teleportation.
Cheat a litte? I've several times changed the encounter's statistics mid-encounter just to make it more exciting and last longer, but I would like to avoid this if possible.
Environmental factors? Trying to make the players multitask always makes encounters last, but that only works on tactically smart players. Most players will figure out riddles and puzzles, but can't figure out why assaulting a castle without a plan might be a bad idea.

[demigodus]

If you are using buffing spells, have the target also have a Ring of Counter Spell (costs 4,000gp on the SRD), with Dispel Magic, or Greater Dispel Magic stored in it. First dispel doesn't go off.

Ask your players to make characters that can survive taking a hit. (The problem is, optimizing to 1-hit kill, is easier than optimizing to not die in one hit).

Target their weak spots, preferably with attacks that won't kill. So, for example throw a bear with the mage slayer feat at casters, and grapple them out of the equation.

Targets that do lots of subdual damage (there is a metamagic to make your spells do subdual in the BoED I believe, there is a weapon enhancement for it, etc.).

Dimensional Anchor casters, and drop a solid fog on the party. Or other crowd control effects.

A group of enemies, some that just crowd control the party, while the rest do slow but steady damage. Force the party to take out the crowd controllers first. If you give us a list of your party's abilities, you could get suggestions on how to shut down their main shtick, forcing them to fight without it. At which point, hopefully they do a lot less damage.

Don't just meaninglessly raise SR. If you are going the route of the SR, use a golem or two (preferably that can fly, or have ranged attacks), but otherwise SR is just annoying in my opinion.

[rot42]

If they are consistently punching above their weight, move down a line or two on the XP tables until it roughly matches the system's expectations - if an "at level" encounter is a few CR higher than their average level, so be it. Of course, this makes it even dicier to try to gauge the danger level of an encounter, but it sounds like your party would make mincemeat of single large beasts so waves of tough but individually less dangerous foes are probably up your alley anyway.

See if you can split their attention, perhaps? A foe who spends rounds destroying treasure does wonders for concentrating player actions.

Add ablative defenses. The defensive Tome of Battle maneuvers work well here: "Sir Damagealot executes a magnificently well placed strike, his blade driving straight for the living heart of his foe, who twists his sword with preternatural speed to deflect the blow."

Some of the [Monstrous] feats can really synergize with a monster's abilities better than many of the out of the book choices.