Characters of this heritage are not native to the world they live in. Through some event, intentional or accidental, they emigrated. Their true home shares the same name and largely the same geography as this one, but the histories differ in subtle ways.
The first mirror worlders were eonics whose time travel abilities malfunctioned, setting them adrift. The phenomenon repeats randomly as tears open in reality, suck beings through to a different world, and then close. Mirror worlder characters can be difficult to differentiate from native residents of an area. Often the difference between their home reality and their new one is so slight that it takes time to realize they are no longer in their original home. Their friends and loved ones aren’t quite the ones they remember. Things they know to be true aren’t quite anymore.
Mirror worlder characters primarily adventure for one of two reasons. Either they want to find a way back home or they want to explore their new world and find out how different it is from the one they are used to. The former tend to be secretive and a bit paranoid. The latter tend to be energetic and gregarious, keen to see what is over the next horizon.
Object Impermanence. While you use your Skim the Parallels feature, as an action you can pluck a single object you see in the reflection into your hand. An object taken in this way must be nonmagical, have a value of less than 20 gp, weigh 20 pounds or less, and be able to be carried in one hand. The item remains in your possession for a number of rounds equal to your PB before returning to its proper reality. You can extend the duration by 1 hour by gaining a level of exhaustion.
Alternately, you can take the Interact with an Object action using the reflection. You can manifest that interaction in your world by making a successful DC 25 CHA (Persuasion) check to overwrite your reality. For instance, if you are faced with a locked door in your world, you can Skim the Parallels to find a reality where that door is unlocked, use your Object Impermanence feature to open the door, and make the CHA check to effect that change in your world.
You can’t use this feature if any creatures other than yourself are reflected in your viewing surface.
Skim the Parallels. As an action you can look into a reflective surface, such as a mirror or a basin of water, and see a mirror world version of your location. While you do, you can use your action on each of your turns to change the image reflected to a different mirror world. The more times you switch the view to a different world, the les subtle the differences are.
Many mirror worlds appear to be the same as the world you reside in, except a door may be unlocked, or open instead of closed, or different items lay on a table in view. You can view parallel worlds through the reflective surface while you maintain concentration, for up of 10 minutes.
You can use this feature to find a particular object or circumstance. When you do so, roll percentile dice. The result is the number of different worlds you must skim to find what you want. Once you have used this feature, you must finish a long rest before you can use it again.
Warped History. When you make an INT (History) check, roll a d4 and subtract the number rolled from your check total. When you make a CHA (Perform) check to tell a story, roll a d4 and add the number rolled to your check total as you add details from your own world’s history to strengthen your narrative.
Languages. You know Common and two additional languages of your choice. Typical mirror worlder characters learn Draconic and Giant.