We already heard hints towards MP-28 being Hound, so who knows, the shoe might just fit...
UPDATE
Thanks to Seibertronian Sabrblade, as well as various social media comments, it looks like this one should possibly move from being taken with "many handfuls of salt" to "the entire salt mine". The new information is found below:
Sabrblade wrote:Allow me to shine some light on something:
See the yellow text that says MP-29 - ???? ?
???? = Haundo = "Hound"
Yep, that silhouette sure does look like Hound, alright.
Hopefully this update doesn't make anyone too disappointed, but while a Masterpiece Arcee isn't outside of the realm of possibility, it's not looking like this image is any sort of proof that it's happening either.
