Here is Blast here is his theme music [link] He is Sonic's pride and joy and he is the Fastest Thing Alive and he is mainly a showoff kind of like Sonic but he is a good guy and helps people anytime & anywhere.
also i'm so confused on how a super fast blue hedgehog and a magical flying rainbow horse had a baby. And also i'm pretty sure that he's not the "fastest thing alive" or else he would be the new santa clause.
HOW DOES THAT EVEN WORK??? I'M PRETTY SURE GENETICS DON'T WORK THAT WAY. And, Rainbow Dash is technically the fastest thing alive as Sonic has been known to break the sound barrier, while Dash can break the mock cone.
Most likely from some pony generator. You forgot to credit it. And like most mlp oc it has to have something over powered with it, for example "He's the fastest thing alive". And seriously sonic and rd getting busy together thanks for putting that in my head.