This is part of my RPG series of entries here at SOB. See the inaugural entry in the series for more details.
In running high level ROLEplaying games, I said:
Lengthy combat seems largely inevitable, except in cases of combats that look like “failures” (either because of TPK or a too-easy vanquishment of what was supposed to be a dangerous foe), in high level campaigns. Lengthy combats don’t have to be boring, or common, though. Mix in combats with lower level peons, along with other types of challenges, and the occasional lengthy combat will feel epic instead of merely long. It’s the boring sameness of lengthy combat after lengthy combat that really makes combat in high level campaigns dull, and that’s easily avoided by making sure that the game’s about a lot more than “challenging” combat.
As I hinted, high level combats can surely get tedious and dull if they turn into blow-by-blow slugfests where both sides are trading damage and soaking it up by virtue of high hit point totals. This is one of the biggest problems with stat inflation as a means of keeping game play “balanced” at higher levels.
Of course, at higher levels both characters with classes and creatures with Monster Manual stat blocks also develop strange and wondrous abilities, including “save or die” spells, frightening supernatural abilities that (temporarily?) cripple opponents, and other capabilities that basically break the rules of normal hit-and-damage combat resolution. Just a few days ago, a tenth level character of mine came within a hair’s breadth of having his memory erased and getting dumped on the street or worse (thank goodness for the save bonus granted by Conceal Thoughts).
Scary insta-kill abilities can sometimes be more trouble than they’re worth, however, as combat resolution becomes anything but predictable for the GM, whose aim should generally be to challenge the PCs without accidentally achieving TPK. Sometimes, PC death is appropriate, but one hopes it’s because of a dramatic turn of events that adds to the power of the storyline, rather than because of an unexpected series of save failures that ends the storyline prematurely with the universal deaths of the entire group of PCs.
The only way I’ve really discovered to deal with this other than to just completely screw around with the basic rules of the game system (which I have been known to do from time to time) is to combine conflict resolution options that avoid the standard toe-to-toe confrontation with the occasional, truly epic battle at a climactic moment that is rare enough to make it fresh and interesting rather than just yet another hit point grind. Lengthy battles of attrition of massive HP totals can be interesting, as long as they’re not commonplace. Break things up with noncombat events that draw the players into the game at least as well as combat encounters, and the variety will help even the most grinding combats become more interesting as well.
In short, there’s a lot more to keeping combat interesting at high levels than merely keeping it challenging.
I guess there’s always the option of just picking monsters that have a lot of insta-kill capabilities and pit them against your PCs, then do all your rolls behind a GM’s screen and fudge the results to keep things fun for the players. I find that saps a lot of the fun from the game for me as a GM, though, and pretty well fails to engage the players in actual roleplaying nearly as much as the kind of approaches I discussed above. Your mileage may vary.