Dash Ring 1-2-3 is the second Challenge Act of City Escape Act 2 in the console/PC version of Sonic Generations. It is unlocked after clearing every Stage in the Dreamcast era and is playable only as Modern Sonic.
This Act takes place within a highly modified version of City Escape Act 2. The stage's layout has been changed with metal girders and boxes, and there are many Spinning Platforms that must now be passed in order to progress.
In this Challenge Act, the objective is to reach the Goal Ring at the end of the course while passing through every Dash Ring that the player comes across. If a Dash Ring is skipped, the next one in the set will not function, forcing the player to backtrack.
The stage is otherwise similar to the normal version of City Escape. The player begins on the road after the section where they would run down the building in the normal Act, where they then continue while navigating through the boxes, Spinning Platforms, and obstacles. They are then placed in the 3D section with the staircase before reaching the Goal Ring.