I am still struggling not to jump on furniture a full week after the announcement.
Thinking about this in terms of recent developments, as a ShadowPala cardfighter I'd much prefer that this be some form of Blade Liberator derivative with continuous +1000 in the vanguard circle (Javelin in the soul as a nostalgia throwback?), then a retreating FVG with its own unique skill (or a Kyrph or something) but this could also be part of the new model of evolving card, i.e. what Genesis and Bermuda Triangle are getting. Fullbau-Javelin-Blaster Dark were the series of cards to introduce the original mechanics, so it won't surprise me if Bushi does go with that, but even if they do I hope that he has a V/R retire skill. Somehow.
In terms of what kind of subgroup they could be going for with this, two major possibilities arise in my mind; sharing the Liberator mechanic with Gold Paladin as a throwback to BT05's cross-clan Blaster support (and revenge for Royals hogging the only cross-clan support back then) or some kind of "imprisoner" opposition to the Liberators like...Dictator. That would make my day. Blaster Dark Dictator. (This will not actually happen outside of my ideal world but a CoCo-style revival of Dictator would be cool since he just got a second run in Japan's promos.)
After all this wait I am determined to have my Dark and eat it too. +1k VG circle and V/R CB2 to retire, those are my only demands, I don't even care if it's grade 2 or lesser or requires you to have a Darkberator vanguard.