A team has finished a game with 12-21-2 runs-hits-errors line 9 times since 1897, most recently Boston Red Sox on 4 July 2016. That is about one every 49,222 team-games.
Box score for the most recent one ↗
12-20-6 12-20-1 12-20-5 12-21-0 12-21-5 12-21-6 12-21-2 12-21-1 12-21-3 12-22-3 12-22-2 12-22-0 12-22-1
The whole distribution — Runs-Hits-Errors Lines · All 18 shapes