I'm using a version of the "Story Based XP" variant. My concept runs something like this:
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Story Award XP:
Sources of XP in play-
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Overcoming challenges while working towards a goal.
Examples:
- "Relevant" combat
- Gathering Information/Clues
- Skill Use (Disarming traps, Bluff, etc.)
- Forming Strategies/Tactics
- Solving Puzzles/Mysteries
XP earned for overcoming these challenges will depend on two main criteria;
1) How difficult the challenge was, and
2) How much overcoming the challenge mattered to achieving a goal.
Factors taken into account might include: physical risk (combat, traps, etc.), DC of any skill checks or saves necessary (Will Save, Bluff, Search), etc. This is left largely up to the DMs judgement. Combat that helps meet goals and progress the story are "relevant," just looking for mosnters to bash isn't.
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Roleplaying and "Story support."
Examples:
- Actions and decisions consistent with character and goals.
- Keeping player and character knowledge distinct.
- "Flavor" injections into game (Speaking in character, etc.).
XP earned for RP is not as much as for challenges and goals, but actions wildly inconsistent with a character's personality, etc. will lessen the value of any stated goals. Also, the campaign will be taking stated PC goals into account, so playing a character consistently will give them more goal-related adventures and thus more opportunities for XP awards. The criteria for determining awards for RP will be based primarily upon how consistently your character is played "to concept" and making an effort at "fitting" the character into the campaign world.
-
Achieving Goals.
Examples:
- Story/Campaign goals set by DM. i.e. Finishing a quest, etc.
- Party goals. i.e. Triumphing over a rival group of adventurers.
- Personal goals. i.e. Defeating archfoe, attaining noble rank, etc.
Goals are defined in part by the DM when he makes the adventures and setting. Some goals are defined by the party as they play (i.e. Get items the wizard needs to set up his lab so he can make magic items for the group.). Others are defined by the players when they design their characters (Avenge their father's death, become a knight, marry their childhood sweetheart, etc.). PC-design goals are usually longer term goals. "Get a big-ass sword!" isn't really a goal. "Retrieve the ancestral blade of my clan (after killing the thief messily)!" is a goal.
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Since consistency is part of the RP awards, it can encourage staying in character more. Also, I use a general policy of "If you say it, and it isn't describing an action your character takes, then your character says it
OUT LOUD." A few instances of a metagamer blurting out "Oh, man! This guy has gotta be the villian! I bet he's just hiring us for this quest to get us away from town!" Means the "villian" just heard this comment by the character and may react accordingly.
This can require a certain flexibility on the DM's part and a willingness to improvise, but it can serve as a good object lesson to the players. Though I highly recommend that you make sure the players know this "you say it, you said it" policy is in effect ahead of time. That way, the party shouldn't blame the DM, they should blame the knucklehead who opened his yap in front of the duke!
EDIT: for added explanations