Just as I knew I would, I forgot an entry into my current list of house rules. Truthfully, I probably missed even more, but this is the only one I came across whilst perusing a recently filled notebook. It comes from the superb Blog of Holding, which I love, and read every day despite their focus on a system I don't play. The outline of the system is detailed on a post from July 20th. You'll notice, however, that my version detailed below is significantly different. Brilliant as Paul's idea is, the flaws listed seem at best goofy, and at worst unbalanced.
In most systems, flaws are used as a kind of reverse-feat. The player agrees to allow his or her character to suffer from some frailty, and in exchange, they earn a benefit of some kind. On the surface it seems like an awesome idea, and I recall being very excited about it when I first read about them. As I've gained experience, however, I've come to the conclusion that it's impossible (or at least very difficult) to implement such a system without inadvertently creating unbalanced characters.
This begs the question: why should flaws come with buffs to characters at all? You and I have flaws, and those don't come with benefits. I'm overweight and dropped out of college due to financial problems. That doesn't mean I got to pick "hilariously funny," "devilishly charming," and "god damned brilliant" to make up for being fat, uneducated, and poor. I have those positive traits despite my failings.
Using the rule below, flaws have no upside. And, since only the most hardcore role player would take such a flaw, flaws are also mandatory under certain circumstances. Please note that none of these flaws are overly harmful to a character. These flaws merely enhance a per-existing lack of ability in small, flavorful ways.
Without further ado:
Pathfinder Flaws System
If a character has a score of 9 or lower for any of their 6 base ability scores, they must select a flaw from the list below related to that ability score. For each ability modifier lower than -1, the character must have an additional flaw related to that ability score. For example, a character with a Charisma modifier of -1 must take one Charisma flaw, a character with a Charisma modifier of -2 must take two Charisma flaws, et cetera.
If any of the ability scores with associated flaws are ever permanently increased, then flaws may be removed at the same rate as modifier penalties are removed. If the ability score modifier reaches 0, all flaws associated with that ability score are removed.
Puny: You are treated as though you are one size category smaller than your racial norm with regards to weapon proficiencies.
Weak Grip: Any time you miss with a melee attack your opponent may make attempt a disarm combat maneuver as a free action.
Bad Swimmer: You cannot succeed on any swim check with a DC higher than 10.
Bad Climber: You cannot succeed on any climb check with a DC higher than 10.
Insufficient Block: If you use a shield, you only gain half of its AC bonus. If your game utilizes the "Shields Will Be Sundered" rule, you may not take advantage of it.
Slow Starter: You cannot win an initiative roll. If your roll is ever highest, you move to second place in the initiative order.
Butterfingers: Upon rolling a natural one in combat, you drop your weapon.
Two Left Feet: When moving over difficult terrain, or trying to move over an obstacle, the character must make a Reflex save (DC: 13) or fall prone.
Pushover: Upon being struck by a critical hit, you fall prone.
Awkward Fall: Add +1 to the falling damage for every 10 feet you fall.
Medicine Dependent: You require a daily dose of medication to avoid the fatigued condition. After two days you gain the exhausted condition.
Slow: You can run at a maximum of twice your normal move speed, rather than four times your normal move speed.
Cheap Drunk: Even a slight amount of alcohol, as much as half a cup of weak brew, leaves you impaired. You take a -4 to all Dexterity checks & Wisdom checks until you've rested for 8 hours.
Weak Frame: If you wear any armor in excess of 40lb, you are treated as encumbered.
Illiterate: You cannot read or write.
Ignorant: You cannot succeed on any Knowledge check with a DC higher than 10.
Inexpressive: You take a -2 on any check which requires you to express yourself to another. This includes Diplomacy checks, Bluff checks, Perform checks, or any abilities or spells which require a subject to understand the character.
Bad Eye for Value: You always pay 10% more than market value when buying items from merchants. You always sell for 10% less than market value.
Tempted: Select a temptation from the list below. Whenever presented with your temptation, you must make a will save (DC: 10 + Your Character Level) or indulge in that temptation. This flaw can be selected more than once, its effects do not stack. Each time it is taken, select a different temptation. List of temptations: Alcohol, Food, Sex, Drugs
Overly Honorable: You cannot make bluff checks.
City Slicker: You cannot succeed on any survival check with a DC higher than 10.
Day Dreamer: You cannot succeed on any reactive perception check with a DC higher than 10.
Spendthrift: For every day your character spends in a town or city, he or she loses 1d10/level gold on purchases of food, drink, and baubles.
Gullible: You cannot succeed on any sense motive check with a DC higher than 10.
Rude: You're unable to bite your tongue. You cannot succeed on any diplomacy check with a DC higher than 10.
Meek: You're unable to assert yourself. You cannot succeed on any intimidate check with a DC higher than 10.
Magically Inept: Any successful Use Magic Device check has a 25% chance to misfire, causing the target to be determined randomly. If the target is self, the spell merely fizzles.
Bad With Animals: Animals which encounter you are unusually aggressive towards you. Those which would normally be friendly are unfriendly. Those which would normally be unfriendly may attack you.
One of the best things about this house rule is that it is nearly endlessly extendable. The flaws are both simple, and entertaining to come up with. As much as I like it, however, it really isn't for everyone. Players will almost always be resistant to something which reduces their effectiveness. As always, the best policy is to work out what works best for your group, as a group.