Notes:

J. Michael Tatum (Sebastian Michaelis from Black Butler, Scar from FMA Brotherhood, Kyoya Otori from Ouran Highschool Host Club, Owl from Deadland Wonderland, Erwin from Attack on Titan, Nishijima from Mirai Nikki, France from Hetalia etc.) is playing Klein (Weiss' butler, just so you know).

Christopher Sabat (Vegeta and Piccolo from Dragon Ball, Armstrong from FMA/FMA:B, Zoro from One Piece, Jigen from Lupin the 3rd etc.) is playing Dr. Watts.

Josh Grelle (Armin from Attack on Titan, Yuki from Mirai Nikki, Ginoza from Psycho-Pass etc.) is playing Tyrian.

And Chris Guerrero (Cooler in Team4Star's DBZ Abridged and Enrico Maxwell in Hellsing Abridged, Gecko from One Piece, Ichiya from Fairy Tail, Katsuya from Tokyo Ghoul) played the Faunus Blacksmith.

There's also Mike McFarland (Master Roshi from Dragon Ball, Goemon from Lupin the 3rd, Jean from Attack on Titan etc.), but he wasn't in the first episode.