Bear I'm guessing that much like Guilty Gear some are blockable, some unblockable, some super close range and some far (like Kanji's looks like a throw). In GG you activate it by pressing 4 buttons at once (for any character) then inputting whatever their unique move was, you could also only activate once per round and if you missed it you're...I was about to say "sol" but then as I was talking about Guilty Gear I though of Sol Badguy and was like "heh..."
In any case it also looks like you need a full super in this but I wonder if it needs a special activate or only once per round etc...course getting a full bar twice in one round usually isn't that easy anyway.
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"May the earth shatter, may the oceans dry, and may the sun extinguish itself. We are demons."