This was a solid first episode for the new series created by Genndy Tartakovsky; featuring an interesting premise, also with an interesting, pretty unusual cast instead of merely following stereotypes.
I mean, the battle between good and evil is perhaps the most overdone type of story made by modern fiction, but Genndy knows how to give it a certain "special touch" that only can be expected by the same man that brought us Samurai Jack and Primal.
Such a shame this show had to be moved to "Adult Swim" instead of Cartoon Network despite not having any real "objectionable" content, but it seems that nowadays kids shows must be only mindless fluff without a single trace of intelligence or subtlety. A shame, because I grew up with many great animated series that still haven't lost their charm.
In other times, this would have been as big as Samurai Jack was back then in the day.