It would be easy to have come up with «roguelike plus
rhythm» and end there, but tweaks to the
model include compressing the
game into four distinct worlds (so you can achieve some progression even if you don't beat the
game first try), adding new characters who change the structure (one has no weapons; another can not pick up gold) and breaking out boss battles to a separate level entirely.
Summary: Soul Fjord's unlikely concoction of brawler,
rhythm game and Rogue - like largely works, thanks to pleasing gameplay and a micro-transaction
model that's equitable.