Score is a scrapped mechanic in Super Mario 64 only present in some personalized copies. It appears below the power stars and lives on the HUD, and is usually a series of 5 digits, with the maximum score most commonly being 99999. The score resets upon leaving a level, and it appears in place of stars on the score menu on the file select screen, as well as in place of the maximum coins collected in the mission select screens.
The score can be increased by obtaining 1-Ups, defeating enemies and bosses, collecting coins, secrets, as well as collecting stars. Upon reaching a certain score when leaving the level, the player can obtain a 1-Up. Notably, one report states that obtaining a high enough score can award the player with a star in place of the 100 coin star.
Notably, some new collectibles can occasionally appear in copies with the anomalous Score system, most commonly being Mushrooms, though other things can appear, such as special forms of coins, or smaller power stars. Rarer forms of these collectibles have been reported that give temporary score multipliers, that make the player obtain more points than usual.
Score Overflow[]
The score system is usually extremely glitchy, so sometimes an anomaly like Score Overflow can happen. Score Overflow is an anomaly that can happen when you try to go past your maximum score. When this happens, the score values overwrite other values in the game, like how many 1ups or coins you have, or even the AI itself. If the score values corrupt the AI, it could go into a state of AI Degradation.