If Mindy Kaling is slated to appear in Episode 10 of Season 13, it’s possible that she’ll have a pivotal role.
The last five seasons of Always Sunny have run for ten episodes each; assuming Season 13 also runs for ten episodes, Kaling would be appearing in the Season 13 finale.
Even if Kaling does appear in front of the camera on the show, there’s no guarantee that she’ll reunite with her former Mindy Project love interest Glenn Howerton.
Howerton won’t be around full-time in the next season, and we still don’t know how much of him we can expect.