This game is unique to all others in the series in that collecting every item will not guarantee the good ending. In fact, 200% Completion of the game (collecting every single item, including temporary ones) doesn't even meet the requirement. In order to trigger the Good Ending cutscene you must have traversed an estimated 290 screens of Super Dimensional Space by the time you beat Bloodstained Planade G. A "screen" is a 2x2 unit square on the Map. These screens do not all have to be unique, meaning you can backtrack through previously activated SDS screens to meet the requirement.

Here are the minimum numbers of unique SDS screens the following approaches will encounter: Any % - 175 97% - 214 200% - 266