You know who this is! The Ghost Rider from the 70s and 80s! He's back with a vengeance and will act as Danny's mentor throughout the series. He will start off as just human and his original intent was to kill Danny as he believed that the Ghost Rider that emerged in NY was Zarathos. Eventually, Zarathos will become bonded to him once again and he will join Danny in stopping the demonic invasion of NY with other allies. In time, he will find out that Danny and Barbara are his long lost siblings and that Barbara was supposed to be the Ghost Rider and not Danny.

For his human voice, he's a tad older than Danny, so like early to mid 30s sounding should be what you shoot for. For his Ghost Rider voice, DO NOT do an impression of Fred Tatasciore. Danny's Ghost Rider will sound like the Richard Greico's (UMvC3) version of the character. You can do anything as long as you do not sound like how GR does in MvC: Infinite or Ultimate Alliance 3.

Some References:
Crispin Freeman or Steve Blum (Marvel Super Hero Squad Online)
Mitch Urban (Marvel Heroes)