Many DMs and Players wrestle with HP and Hit Dice scaling problems, with characters becoming too much like superheroes. Depending on luck and bonuses, even mid level characters can have absurdly high Hit Points. Characters who are supposedly normal humans must be stabbed dozens of times, receive multiple crossbow bolts to the head and set on fire before they say “Maybe I should pace myself a bit!” Apparently, hard work and a vigorous regimen of calisthenics can render a human being more durable than dragons! This is a frequent game-world-breaking complaint I hear. It gets to the point when the only way PCs are challenged is by stupid high-level wizards or throwing so many giant monsters at them simultaneously that if such a horde were to really exist, it would seriously upset the ecological balance of a region.
Then I recall reading somewhere, and I really wish I could remember exactly where, so I could give them credit here, that some early D&D groups never moved beyond Holmes Basic, content to play three levels, where achieving level four was a superhuman achievement beyond comprehension. Still, I don’t think that capping your players at level 3 is an optimal solution, simply because for so many players, gaining levels is part of the incentive to keep playing: getting stronger and getting better. However, there is another option: Cap Player Hit dice early.
Hit Dice and HP are abstractions that offer little realism for combat. I’ve read a lot of interpretations of what they represent, such as the character’s ability to survive a blow or some sort of measure of willpower and endurance in the heat of combat rather than actual wounds. Lots of special rules for Killing Blows have evolved to try to compensate for the fact that the base damage of a weapon, that in real life would cause lethal damage with one good strike, is often unable to do so against characters or monsters with more than 3 hit dice. It’s up to the DM to describe what the mechanical outcome translates into narrative terms. Here are a few examples:
Orc does 8 damage w/longsword to 7hp lvl 1 fighter – “The Orc runs you through with his longsword; the fighter spurts forth blood from his mouth before collapsing dead.”
Orc does 8 damage w/longsword to 40hp lvl 5 fighter – “The Orc lands a grazing blow with his longsword, opening a gash on the fighter’s shoulder.”
Orc does 8 damage w/longsword to 84hp lvl 12 fighter – “The Orc’s blade catches a small exposed spot on the fighter’s armor, drawing blood.”
Mechanically, the exact same thing happened from the orc’s end. He’s put forth his very best within the constraints of the game, but as the player’s level increases, the effect of any blow landing with full force becomes lessened, eventually to ludicrous outcome.
Now think for a minute about any high fantasy that you’ve read. Most of the characters, no matter how good they are, either a)avoid fighting when they can, b)don’t get hit in fights, or c)get hurt really bad or die when someone actually stabs them, unless they have literal magic plot armor. This is why any time people stat out Lord of the Rings characters, they generally end up with a Fellowship of level 2-4 characters led by a level 5 or 6 Gandalf.
Okay, I’ve been rambling for a bit now, I think. Let me cut to the nuts and bolts of my suggestion.
-Cap Hit Dice at level 3. Maybe allow for a +1 or +2 to HP or Constitution bonus per level depending on class.
-Allow progression of spells beyond level 3 for magic user classes/races. Still the weak, squishy mortal wizard, but with powers far greater than any non-magic using mortal could comprehend.
-Allow progression of class & combat skills. Fighters get better at fighting, thieves get better at thieving, halflings get better at… halving? Characters can develop phenomenal skill in their chosen fields, perfecting their trades, but are still limited by their constraints of being hominids.
-Allow for progression on the Saves tables, because these are based on class skills, training and experience.
What are the practical effects this will have on your gameplay?
The world will never lose its sense of danger for the players. Large monsters, such as ogres, trolls, and, of course, dragons, will always pose a serious threat to those who hunt them. Even Beowulf, after two very successful dungeon crawls, got killed by a dragon. Additionally, smaller common monsters will never lose their threat. If players can’t mow through demi-humans like dry grass, they can remain a significant menace throughout a campaign without having to house-rule them or give them their own Levels.
Combat will have more risk and therefore encourage better planning and strategy than simply running in and dishing out a lot of damage really fast, having tanks soak all the melee damage, and sit around and heal those dozens of lost Hit Points.