Shanghai IV: Ryūmon Hiyaku, the sub-title loosely translated to "Dragon Gate Leap", is a mahjong solitaire game developed and released by Success (under license from Sunsoft) for arcades digitally via the ALL.Net P-ras MULTI Version 3 service for Sega's PC-based ALLS UX hardware on March 16, 2023.
It is the fourth numbered arcade installment of the Shanghai series of mahjong solitaire games, bringing it back to its traditional roots with a single no-gimmick single-player game mode. It features both standard arcade controls (with a button to help speed up the cursor) and touchscreen controls.
Players progress through 20 stages of unique layouts and are scored based on their speed, with a global leaderboard for those using their supported IC card. As with traditional arcade games in the series, players have a countdown timer to work against (which replenishes on matches) and multiple assist power-ups to work with (including one to automatically match a a pair, one to peek under tiles, and one to show all available matches). Completing stages 5, 10, and 15 throws players into a bonus mini-game based on concentration to earn additional power-ups and score.