Prototype: hard stop + follow-up questions (round-4 Nc2 case)
Prototype: hard stop + follow-up questions (round-3 Kg2 case)
Prototype: branch explorer — straight to the moment, pick lines, step back (round-3 Kg2 case)
Prototype: branch explorer, minimal intro — only the essentials, then straight to the choices (round-3 Kg2 case)