Sonic Boom: Fire & Ice Rings charts could use some clarification for competition rules. The main levels have a Challenge Room that is only accessible as long as the item within has not been collected. Exiting the Challenge Room by collecting the item or via the menu will reset the rings available in the level, whether or not they have been previously collected. A site rule prohibits collecting the same rings more than once which prevents players from reaching 999 rings on these levels. However, allowing one entry into the Challenge Room creates the problem that players have to either avoid rings that were previously collected or keep track of recollected rings and subtract that value from the total. As far as I could tell, three of the levels have rings that are unavoidable, forcing the player to recollect some rings, and most other levels require going out of the way to avoid these rings.
With that said, these are some recommendations for rules for Rings charts, in order of my preference:
* Prohibit access to the Challenge Room (Keeps competition simple, but cuts out the rings in the Challenge Rooms.)
* Allow the Challenge Room, limited to one entry, and allow collecting the rings that respawn (May be somewhat arbitrary, but avoids any problems with tracking rings that are collected twice and keeps the Challenge Room rings open for competition. Backtracking might add to the difficulty in competition.)
* Allow the Challenge Room, prohibit collecting rings more than once (Requires attention to which rings are collected. Some Challenge Rooms would be inaccessible without new discoveries.)
* Allow the Challenge Room, subtract rings that are collected more than once (Requires attention to which rings are collected and displayed ring total will frequently not match the value submitted to charts, but keeps the Challenge Room rings open for competition. Backtracking might add to the difficulty in competition.)