Add a player to a scoreboard if they aren't already on it

Sadly, I couldn't find this answer anywhere.

I'm going to refer to [score_deaths=1] as selectors, as I don't know their proper name.

Is there a selector for if a player isn't on a scoreboard (f.e. @a[score_not_on_deaths] or @a[score_deaths!])

Or, even better, is there a way to say player A just joined, he isn't on the scoreboard, /scoreboard players set A deaths 0

Is there a way or a workaround? Also, this is using a /fill clock, so you can only use one command. Thanks!

Best Answer

You can add all players to a scoreboard and keep all other players unaffected by adding 0 to the score for everyone:

/scoreboard players add @a deaths 0

All players without a score will have their score set to zero. All other players will be unaffected.

Managing Teams

To add a team (in Minecraft 1.12 and older): /scoreboard teams add <teamName> [displayName]

To remove a team (in Minecraft 1.12 and older): /scoreboard teams remove <teamName>

To assign a player to a team (in Minecraft 1.12 and older): /scoreboard teams join <teamName> [player]

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