A cropped image showing the Score Display option in Brawl.
The Score Display option in Brawl.

The Score Display is an optional rule that is available from Super Smash Bros. Melee onward. It is unlocked during Versus Mode by scoring a total of 5,000 KO's in Melee and a total of 200 KOs in Brawl and Super Smash Bros. for Nintendo 3DS; in Super Smash Bros. for Wii U and Super Smash Bros. Ultimate it is available from the beginning. When this rule is switched on, the net score of all combatants will be displayed on-screen next to their series symbol. The Score Display appears in Time matches for all games following Melee (always appearing when viewing replays), in Bonus matches in Melee, and also appears in Stock and Stamina matches in Ultimate. Oddly, in Bonus mode, it displays the same score as if it were Time mode, not the amount of Bonus points collected.