I recently wrote about GM PCs over at Know Direction. One reason that I personally use them is to bring the number of PCs in a party up. That said, a GM PC is not the only way I have changed the party makeup to allow a smaller group of players to fill the classic 4 PC party. One idea I tried many years ago, was to let players create two PCs that were linked via telepathy and had some extraplanar heritage, such as aasmimar or tiefling. The premise was that their souls were too powerful to inhabit only a single mortal body, and so they became twins that were mentally linked. I wanted a simple solution to the metagame issues of having one player running multiple characters. We didn’t want to roleplay them talking to themselves, but we also didn’t want to spend a lot of time tracking what each character knew. Recently, I started thinking about ways in which to accomplish similar results within the confines of the rules. Let me know what you think.
Twin feats grants identical twins abilities that are unheard of in normal siblings. Additionally, like teamwork feats, they only function when both characters have the feat and both characters are able to use the feat.
Telepathic Look (Twin)
You and your twin can communicate telepathically with each other by simply sending a look.
Effect: As long as you and your twin are within 100 feet of each other with clear line of sight, you may communicate telepathically. Because you must look at each other to do so, a sense motive check can alert viewers that you are up to something. The DC of this check is 10 + your level unless you attempt a bluff check to hide it.
Status Link (Twin)
You and your twin always know where each other is and what your general conditions are.
Prerequisites: Telepathic Look
Effect: You and your twin are always under the effect of status. If one twin is reduced below 0 hit points, the other twin immediately takes subdual damage equal to half their current hit points. If one twin is killed, the other twin immediately takes subdual damage equal to their current hit points.
Twin Rage (Twin)
You know when your twin is mortally wounded and it sends you into a rage.
Prerequisites: Status Link
Effect: When your twin is reduced to negative hit points or is killed, instead of taking subdual damage you instantly fly into a rage. This rage lasts a number of rounds equal to your level. If your twin returns to life and consciousness, the rage ends immediately. Either way, you are fatigued after the rage ends.