I am going to be implementing a skill point system in my game. Whenever a character levels up they can put a point into defence, offence, speed, and potentially other categories if it seems to fit.

My question is if anybody has had any experience in knowing how to make points translate to actual stats.

The three curves I am considering are

1. A snowballing curve, like an exponential or quadratic curve. This would discourage players from making balanced characters, instead they would try to get a character to specialize. Example, a character with 2 points in attack and 2 in defense would see an increase of say, 100 in actual stats for both attack and defense but if they put all 4 in one, they would get 400 stat increase 200 < 400, so you get more bang if you specialize

2. Diminishing returns curve, like a logarithmic or sqrt curve this would discourage specialization. If you were to dump all your points in one stat you would have less total benefit than if you spread it out.

3. Linear curve. Don't punish or reward the player for specialization with the stat curve. 1 point anywhere will always give the same net benefit.


Has anybody had any experience trying to balance stat points like this? Any good example in games? I figure I can even make different characters have different stats curves if I wanted to. I just wanted to start a discussion on how the stat curve effects the player and of any of the 3 curves above should be avoided.

I don't know what will work best for your game but personally, as a player, I don't like feeling as though if I make the wrong decision assigning points that the game will become unwinnable. For that matter, I don't really like feeling as though I might be missing out on something cool. I want to experience as much of the game as possible. So, the only time I tend to feel comfortable specializing is when I have other party members around that can provide whatever skills I might be missing.

This is a game where there are multiple characters on your team

I recommend interpolation between design objectives: at certain points of the game, some reference character "builds" should be both equally strong (unless there's a good reason) and equally expensive. First balance how valuable the stats are; costs will follow. Using a computer allows unlimited complexity of the cost model, without the compromises of tabletop roleplaying games.

For example, suppose character stats are brutality, spellslinging, dexterity and toughness and expected character types are wizard (very high spellslinging, very low brutality), dumb fighter (high brutality and toughness, no spellslinging), technical fighter (high brutality and dexterity, low spellslinging) and ninja/sniper (very high dexterity, medium toughness, low spellslinging). The expected stats (B/S/D/T) of a starting character with 100 character points could be 2/12/4/4 for a wizard, 9/0/6/8 for a dumb fighter, 8/2/7/5 for a technical fighter, 5/2/12/5 for a ninja. Obviously, these values need to be validated by playtesting (including playtesting that weird character types are either as good as standard ones, or inferior for obvious reasons, e.g. insisting on average stats and getting neither a bonus melee attack for high brutality like a fighter or an extra spell package for high spellslinging like a wizard)..

After a while, the characters are supposed to have 600 character points and "normal" characters are expected to improve their stats: 4/18/6/6 for a wizard, 15/0/8/9 for a dumb fighter, 12/3/9/9 for a technical fighter, 7/4/16/7 for a ninja. If, like in this case, the sum of the stats of every character type is almost equal, the cost curve could apply to the total of a character's stats: the first 23 stat points cost 100 character points, the next 10 stat points cost 500 character points. (for example, assuming a quadratic curve, a*SP*SP+b*SP= CP, gives a linear system: a*529+b*23=100 and a*1089+b*33=600).

it depends on the exp cost for a level. assuming its exponential,

case 1 will cause players to become very powerful at their specialization very fast - probably causing imbalance. a runaway train of increasing specialized power. their power may increase more or less linearly with exp if the exponential level costs and exponential bonuses cancel each other out..

case 2 will nerf high level progress. big time, exp costs increase exponentially, but bonuses decrease exponentially. probably only use it if they hit cap too fast.

case 3 is the standard way to do it with exponential level costs. leveling is exponential, and the bonus at each level is the same. each bonus point takes more exp to earn than the last.

I think you've asked a bit of a trick question there. Asking how a tool should be designed requires knowing what it's going to be used for.

It also depends on what kind of feel you're going for with the game though too, if its supposed to be relaxed or punishing? The steeper the curve the more punishing, and the less notice the player has to adapt their skills to the new environments.

One answer is somewhere along the lines of "determine the perceived difficulty curve you want the game to have from start to finish, determine the player power curve over the game, create the actual difficulty of the levels using a curve that is the player power curve added to the perceived difficulty curve. So long as these are consistent then your question about picking the curve type really only matters if the player makes their character too unbalanced, though if they screw up majorly it shouldn't matter if they have the option of backtracking and grinding on some lower level enemies until they fix their build mistake.

If every level you double in strength but the enemies double in health you've got no difficulty curve there, but you can increase the number of enemies and combination of enemies to make up for it. Part of giving the feel of progression is throwing in the early enemies that used to be hard to kill so the player can wipe the floor with them as the old bosses become the new standard minions. That way the player feels like they have grown more powerful even though the game is getting more difficult. That's one reason why I think elder scrolls progression system kind of sucks, scaling monsters to match player progression removes the feeling of becoming more powerful and it breaks the immersion by making the whole thing feel too artificial. It also penalizes players who don't want to focus on combat, either allow that as an viable option or don't allow skills that don't improve your combat.

Additionally skill points should all be lumped in with the treasure curve too. Attack and defense skills are "lowering enemy defense and attack effectiveness" skills, while healing and crafting are "lower the enemy defense and attack effectiveness a greater amount for additional cost" skills. Your money is effectively a second attack and defense improving statistic that has to creep along in time with the skill points. This also means you have to be very careful about what level of drops you get, and their frequency, compared to things you can craft if you decide to have crafting.

One problem with rpg design is the mini-nuke hoarding problem, that players don't know what the future is going to bring so they try to save powerful ammo even at bosses because they don't know what the game is going to throw next. Possibly an ever bigger boss after this one so they'll regret spending it now. I bring this up because players don't know what is coming up so they've no way of knowing what the best stats will be, so really it's not fair if the game is too punishing because of it. Eg, suddenly there's a new enemy that slaughters you if have one of your skills at level 1, such as being too slow to either dodge or hit a new very fast enemy or the new enemy's surprise attack 1-hit kills you if you haven't put any points into health. If that's the case it might be best to make sure there's an item currently available in the shop that boosts whatever the player is lacking in, so they can always fall back on equipment to make their stats flexible, or maybe a ranged weapon that basically allows them to pass that kind of enemy for money until they have a chance to adapt their skills.

One idea I'd like to see more of in rpgs is getting experience from your failures. You burnt the food but you got twice the cooking experience as a result. In life your failures can teach you more than your successes, and if done well it can help the player along when they need it. Of course it has to be handled carefully so that it's not gamed by continually killing yourself or something but there are many creative ways you can include to balance out or compensate a bad build.