Character Concept: Luxon & Bradyon
As a representation on a unique spin of the Sight Sharing concept that the Lati siblings have in Heroes - great movie btw - insert the blanket term “Valiancer” to describe a subset of the Lati race with a unique potential to evolve that ability into something more. Then focus on two latis in particular, one red and one blue.
The red one has been a veteran of combat for a long time, having gone into service among the front lines of a desperate war - even despite her Legendary status and heritage - in order to prove herself to her hardline father. She’s an expert in combat but only after stripping herself down to the bare essentials and literally putting everything into it at the cost of all else, believing that with the power involved with being a Valiancer she can protect her little sister... and get revenge on the enemy forces who raided her town and destroyed it, killing her mother in the process.
The blue one, however, is a victim of Dialga- and Celebi-related shenanigans - he never asked to go through the troubles time travel creates, but it was at the behest of a beautiful cresselia from the future who came to the past to bring him forward, stating ‘Bradyon is waiting.’ Despite being thrust directly into a protracted battle, the blue one was also recognized as having the potential to be a Valiancer, and as such the heat of the moment resulted in the Red and Blue latis activating this advanced version of Sight Sharing... the Coupling Effect.
By sending their thoughts at least one nanosecond into the future in order to prevent the time lag caused by the Effect’s time-to-exchange, and to offset the bulk of mental information, the pair were able to use the Effect to great effect - sprouting cool as fuck energy shrouds, moving as fast as Mega without going Mega, and allowing the blue one to obtain all the same combat experience as the red one. As time went on, the Effect developed until the red Bradyon (the latias) can use Luster Purge and the blue Luxon (the latios) can use Mist Ball, among other things.
Point being, it’s cool. Change my mind.