Early game · first 8 minutes
Keep enough distance that Billy cannot reach you with Bashdown and a heavy attack together. Move a bishop through him as he gets closer, and save a dash for getting away.
Solomon vs Billy
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Mid game · Walkers
Use Kingside Knight before Billy reaches you with Bashdown and move back toward your team. If Chain Gang attaches, use cover to break the chain instead of assuming Move Piece will free you.
Late game · Patron
Stay away from teammates Billy could chain to you. When he reaches your team, aim your pieces at him from outside his melee range and protect the ally he attacks first.