During a triple or double battle with at least 2 of the 3 on your side, It adds 10 points to each of their stats.
In a triple or double battle, in consecutive attacks, their attack power will get stronger.
3 siblings (2 brothers and one girl) Were always boasting about how strong they were. So one day they went off to battle the three legendary bird pokemon. The birds attacks were so strong they combined with the rattatas DNA. Thus creating these.