I am actually torn torn between the two groups with a slight lean towards Gigas only because pre-memory loss canon!Tsukasa is almost as evil as the rest of DaiShocker. The only reason why he wasn't considered completely unredeemable was that he happened to have no real interest in the plotting a around him. age is more like he just did whatever due to the fact it was all he ever knew - even his family's retainers were DaiShocker peeps so it's possible that the parents were part of the evil empire.

I may also go with an unnamed group that allied with Gigas or something like that. It's still very much in the air.