The castlevania series does not have much commercials. It just propagates by word of mouth.
Though, I do have to ask this question, if LoS is an all out attempt to mainstream the CV series, why wouldn't you invest some money in actual advertisements? I see this problem with other reboots too. I mean, if you want to reach a new audience, wouldn't sitting back and relying on "word of mouth" from those already "aware" of the series(hence, fans of the franchise) hinder sales and that reach out to a new demographic? Why don't these companies have the gall to actually invest in promoting this games. Really, it's beyond me. There are so many instances I've come across various gamers, years later, which I introduce them to games that they immediately say, "Man, I never knew this game existed. Had I been made aware, back in the day, I would've TOTALLY bought it!".