First of all, no attatchments, but IDK.
Banish all cards in your opponents hand? Thats incredibly OP. Get rid of that.
I would change banishing 1 card to 2, and not having to halve his attack so hes a bit better than envoy of the beginning, because if you didn't do something like that i would just keep envoy of the beginning.
So all in all, under powered and over powered in the different effects
You're right about the effs, but you're not looking at the summoning conditions. -.-
Anyhow, I think this is bad, and no one in their right mind will run it. Why?
-If you draw BLS, and it doesn't get negged, you basically win anyways.
-This thing's summoning conditions require you to run terrible Tuners. The only real way I can think up to summon this in a good deck is Blackwings (Veiler + Gale + BLS). And Blackwings can never afford more Extra space.
This is sorta like Armityle - it has a broken eff, but it's not worth running outside a dedicated deck because it can almost never be summoned and you can win if you have the field required to summon it. In other words, overall bad card design. Not going to say "You should change this to that", except for its name (Chaos Soldier is the OCG name for BLS). That's because making anything related to BLS good will wreck the metagame, and keeping it bad will do nothing either. Why not go make a better Synchro less situational and more versatile, if not balanced?