I think a lot of us gamers think that tabletop roleplaying games are exhilarating at the beginning, but that they tend to taper off toward the end. Commonly, this is expressed as "the problem with high level play." I sense that it's seen as more of a problem in class-based systems that emphasize the goal of leveling up, specifically D&D and similar systems. I've written before about how I think D&D essentially shifts the roles of player and Game Master after level 10, with the players being the "defendants" at the start of the game but changing to the "prosecution" by the end. I think there's more to high level play than that, though, and I think that high level is fun, or can be if done correctly, in both class and skill based systems. Here are 5 ways to ensure high level play for your favourite game is satisfying for everyone.
First of all, no matter how high level a character is, damage still kills. No player goes into an encounter thinking there's no chance of losing. There's always a risk, especially in an imaginary world.
Use that to your advantage. Try luring players into combat with a threat well below their level. Once they've taken the bait, trigger something big. The oil rig they've hunted the low-level gang to self-destructs (that one's from experience), the castle suddenly gets swallowed by a volcano, the abandoned spaceship comes to life and sends disruptive surges of energy through the beings infesting it. Whatever it is, make it hit hard. It's scary no matter what your level when the Game Master shrugs and says "Oh that's not too bad. You just take 71 points of damage."
This isn't an all-the-time thing, it's just a good way to remind players that death is a possibility even for a level 20 player, or a player with a pool of 21 dice, or a player with 10 ranks in a d10 skill.
Other times, the exact opposite approach is the right approach, which leads me to...
The more experienced the character, the more they're likely to have at their disposal. When a character has seen it all, endured every threat, maybe even died once or twice, that character probably has all the skill ranks or all class features they'll ever get. Hitting that character over the head with the biggest creature your favourite bestiary has to offer can get a little repetitive after a while.
Instead, use environmental and external factors as threats. A character might have a hacking skill that's essentially impossible to fail. But that doesn't help against that new hybrid biotech virus that's been going around.
Or maybe a character has immunity to every kind of damage possible in the game. But that's of little use against the magical field causing rapidly increasing levels of exhaustion.
Direct damage gets players' hearts pumping, but it's the environment that keeps them on the edge of their seats.
If it bleeds, it can be killed. So what happens when you don't know whether it bleeds or not?
Sometimes the thing that makes an adventure seem dull is that the threats just don't seem like threats any more. Player characters are practically gods at high levels. They're confident that they can march into the final boss fight, take a couple of swings or cast a spell or two, and win.
The player characters are the boss.
And that's why there's nothing scarier than the unknown.
While players don't understand the nature of a threat, they don't know how to beat it. Force players to investigate, to solve a mystery or a series of puzzles. Sometimes the best high level adventure is the "intellectual" one. Admittedly, those can be harder to run, but there are lots of great authors out there who have perfected the technique of murder mysteries that stand up against even magic users, engaging social intrigue, and more.
There's always been a fascinating link between wargames and RPGs. You don't have to know anything about wargaming to see that its existence is an indication that sometimes scale matters.
What that looks like in an RPG is something you have to figure out for your gaming group. There are lots of great indie wargame rulesets out there, so if your gaming group is interested in a diversion, you could have a minigame in which players go up against you in a literal wargame.
Alternately, you can flood the encounter with distracting hordes of minions. A minion is a low-level clone of familiar monsters, which you run as a single group. The advantage of this for you is that you don't have to run 12 or 18 or 34 monsters, you just run the boss, the generals (the "real" monsters supporting the boss), and the swarm (innumerable baddies).
When players attack the swarm, any hit kills at least one minion. For particularly high rolls, you can choose to have it kill two or three minions. When a player kills a minion, that player gets a token that lasts until the start of their next turn. The token means that minions don't attack that player.
I don't explain any of that to my players up front. They learn by doing, and until they figure that little puzzle out, they're very high level characters who are genuinely afraid of the odds they're facing.
The odds are real, too. For the Game Master, a swarm of minions is a guaranteed hit. Every time. Be careful with that, it can be as powerful as it seems. Sure, maybe the monk and rogue in the party only take half damage, or maybe the wizard has mirror image, and so on, but the swarm mathematically never misses.
If you're playing D&D, the math is provided in the Mob Attacks chart on page 250 of the 5e DMG. If you're playing some other system, here's the idea: Calculate the chance you have to hit your target using 1 baddie. Divide your desired chance (100% hit) by the hit chance, and you're left with the number of minions required to attack the target for a guaranteed hit.
The appeal of low level play is that everything feels risky. You can die. Easily. The chance of failure is real.
High level play loses that urgent sense of fear, but it's a traded for moments of supreme satisfaction. It feels good when a cleric transitions from turning undead to destroying undead. It feels good when a fighter kills a monster in one turn. It feels good when a magic user incinerates a horde of monsters with Fireball.
As important as it is to challenge players at high level, it's also important to recognize the position of player characters in the world. They face fewer challenges because they are the challenge. The whole gaming group should take enjoyment in that.
This is high level play, and it can feel amazing. Sometimes it's bad because there's great evil in our imaginary worlds, but sometimes it's really really good.
Ultimately, both times should be equally satisfying.