Showdown is a same-role match on the same two-player cable as Duel. Parent hub: PDN Single Player Modes · Quickdraw.
Two Hunters or two Bounties jack in when they want rank on the boards in a different way.
Rules are specc’ed on paper; the dedicated Showdown path in firmware is still open. Duel stays the default booth flow until that ships.
Alleycat 2027 Game Design — PDN modes (Single-Player / Showdown)