I couldn't find anything for this season, but Terance Mann and Ja Morant are tied for the most games by a rookie with 10+ rebounds, 25+ points and 5+ assists in 2019-20, with 1 game.

which rookie has the most games with 25 points, 10 rebounds and 5 assists this season
Interpreted as:
Which rookie has the most games with 25 or more points, 10 or more rebounds and 5 or more assists this season?

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