The importance of levels

Even tough it can be said that every RPG in existence is inspired by D&D in one way or another, D&D has a few distinctive characteristics that are hard to find in most of the mainstream RPGs that aren’t D&D or direct clones.

One of this distinctive marks of D&D is the strong correlation between character level and the probability of surviving any given danger. In D&D, level measures survivability – almost regardless of edition. The two most important tools for that purpose are hit points and saving throws. Combat capability is also directly affected, through attack bonuses and more damaging spells. On the other hand, the effect of level on skills and general abilities (encumbrance, languages, etc) varies wildly from edition to edition.

The same cannot be said of most RPGs with point-buy characters. Take GURPS, for example: a character made with 200 points can be more fragile than the character made with 100 points in many circumstances, including combat, and even the same character can go from 100 to 200 points without increasing hit points. 

If you analyze all the things the characters can do (let's call them “capabilities”) and how they relate to levels, you can detect three main patterns (although the distinction isn’t always clear-cut). There are also some subdivisions that are worth mentioning.

1a. Direct correlation: the capability grows in direct proportion to level. For example, you gain 1d8 HP per level or +2 to attack rolls every three levels.

1b. Direct correlation with hard limit: the capability grows in direct proportion to level until it reaches a limit. After that, even if the character can still gain lots of levels, the capability evolves no further. For example, the dwarf in Rules Compendium doesn't improve his saving trows after level 12 even if he can get to level 36 (variant rules) ; the Fighter in Lamentations of the Flame Princess (based on B/X) gets a +1 attack bonus per level until level 9, then no more.

1c. Direct correlation with soft limit: the capability grows in direct proportion to level until it reaches a limit. After that, the capacity still grows, but at a slower pace. For example, in pre-3e D&D you might gain 1d8 HP per level until level 9, and then 1 to 3 HP per level after that.

2a. Indirect correlation: the capability bears no direct correlation to level, but as the character gains levels he gains resources that he can invest in it. For example, a 10th level fighter is no better at Appraise than a 15th level fighter in 3e, but he gets more skill points that he can invest in skills – including Appraise – if he wishes to do so.

2b and 2c. You can have hard limits or soft limits in this pattern too. For example, a maximum number of skill ranks in a given skill. Soft limits with this pattern are hard to come by, which I’ll comment later.

3a. No correlation: the capability bears no correlation to level at all. This usually happens because the capability is basically immutable, or can only be changed trough in-game events, as it happens to abilities in most of pre-3e D&D, and to the capability of a fighter to do damage with a single hit in B/X (although total damage dealt per turn can be raised through extra attacks and greater chances of hitting).

3b and 3c. Whatever limits you have on this capabilities are usually determined in character creation. For example, in most editions abilities are capped at 18 or 20 (hard limit). In 4e and 5e, soft limits are used when buying ability scores with points – going from 8 to 10 is cheaper than going from 12 to 14.

The analysis isn't purely theoretical: it changes how the game feels, marks the difference between editions and might create problems and opportunities during play. Complaints about "linear fighter quadratic wizard" and "hit point inflation" are usually related to this patterns. Whole games can be created by emphasizing some of this patterns and de-emphasizing others.

Let's see some examples.

Some times, leveling up doesn't help... (Source: DCC RPG - Art by Doug Kovacs)

HP inflation, AC stasis

An interesting feature of most D&D editions is that, while HP raises dramatically with level (pattern 1a or 1c), the amount of damage a sword blow does stays basically the same (pattern 3). To compensate for that, BAB raises with level (pattern 1), while AC remains mostly the same (pattern 3). The fighter will attack more often and land more often, but since opponents have more HP, fights won't go any faster because of that. This is usually a feature: since more attacks and more granularity means more options, the game gets more complex as it progresses in levels.

In the versions of D&D that grant no extra attacks to fighters, combat may get very slow at high levels, because BAB doesn't make up for increased HP. Since wizards usually get better damage at higher levels, this doesn't apply to them.

Great balls of fire

In most editions, the Fire Ball spell causes 1d6 damage per level of the caster (pattern 1a). In B/X, HP reaches a soft limit in level 9 (pattern 1c). On the other hand, the Fire Ball allows a saving throw (pattern 1a - direct correlation to level) that halves damage if successful.

A 6th level wizard in B/X and BECMI, with his 6d6 fireball (average damage 21) isn't likely to kill a 6th level Fighter (average 33 HP, assuming 1d8 per level +1 bonus from CON) with a single spell. The chance, in fact, is less than 0.1%. The chance is lowered even further as they gain levels, until the HP soft limit is reached: after that, the fire ball becomes dangerous again, although better saving throws partially limit this effects. The RC dwarf mentioned above has the most chance of surviving a fire ball at level 12 - from them on, it only gets worse.

100 ways to die in a dungeon

One controversial effect of HP inflation (specially when HP follows pattern 1a - direct correlation to level) is how it affects the chance of survival from different sources of damage. There are quite a few people that accept than a 15th level fighter can take more than 15 hits with a sword and survive - since combat is abstract and HP includes the capability of avoiding killing blows - and at the same time get annoyed because the fighter can jump from a height of 100 feet and be sure to survive with no permanent damage.

In 3E, surviving without food or water is basically a matter of HP and level (and, to a lesser degree, Constitution). A 20th level fighter can be sure to survive about a month or more without food. 5E, curiously enough, has two different rules for dehydration and starvation, none of which involve HP. This is implemented in such a way that level may give you some protection against dehydration but has NOT effect on starvation (unless you add more Constitution).

E6, pattern 2c and soft limits

E6 is a way of playing 3e where, basically, you gain no more levels after the 6th, but you can get more feats. One of the goals behind the system is to avoid "HP bloat" that came with 3e using pattern 1a (direct correlation to level) instead of 1c (direct correlation with soft limit) for HP.

This works well for lots of people, but might be unattractive to those who dislike feats. One way of fixing that is using pattern 2c for abilities, as I suggested here.

Pattern 2c, in fact, is one of my favorite patterns, because it encourages characters to expand the number of capabilities (other goal behind E6), but at the same time allows them to specialize if they want to. 

Level is directly proportional to shoulder pads. (Source: Diablo III)  

The old-school inside 4e

There is a lot of talk about 5e being an old school inspired game, unlike 4e, but there are at least a few arguments in contrary. In OD&D, level was the main gauge of almost ALL of the characters abilities: HP, fighting ability, saving throws, skills, etc. There is some evidence (through people that played early on) that not only thieves but ALL classes relied on levels for their exploits.

4e does this by adding half level to almost every roll, so that a 20th level wizard is almost always stronger than a 1st level fighter (pattern 1a). By avoiding patterns 2 and 3, 4E makes sure that high-level characters are noteworthy in ANY situation.

Of course, there are many reasons to consider 4e a new school game, but is curious to notice this particular old school aspect is absent in most other editions.

The odd 5E pattern

Fifth edition has a curious implementation of this patterns, where some skills and saves will get better with level (pattern 1) while others don’t (pattern 3), although the feats may allow you to include more of them in the group that gains bonuses (pattern 2). Because of this, a 20th level character in 5E might look very similar to a regular person where most of her skills are concerned, but light-years ahead when her main capabilities are in question.

This pattern causes problems with saving throws, since the things that attacks STs always get better with levels (pattern 1), while most STs follow pattern 3 (unless you get the right feats). The result is that you are very unlikely to succeed in saving throws at high level, unless you're proficient.

To implement pattern 1a in 5th edition, one should starting by granting proficient bonuses to everyone, all the time, and letting proficiency grant a flat bonus instead (or advantage).

A caveat

This post doesn't concern starting capabilities. By changing the number of HP you get in the first level, you can change a lot of assumptions about the game. But this is a different subject, that deserves a post of it's own. It also doesn't discuss the exact number of HP or the exact bonus that is gained per level, which is also a different matter.

What's the point?

The main goal of this essay is to give you tools that you can use in your own games. How should a 15th level character look like? If you want her to be able to survive a 100 foot fall, use pattern 1. If you want her to be able to survive it up to a point, use 1b. If level shouldn't protect her at all, use pattern 3. The same reasoning may apply to any number of capabilities - should the Fighter attack more often, or should she get better at dealing damage and breaking down doors? Should a high level wizard be stronger than a low level fighter? Should a 15th level cleric be better at sneaking around than a 1st level one?

This might help you understand why you favor one edition over another, and how you can come up with your own house rules for D&D.