As we are now in Season 8, I am again updating the probabilities for each Mane Six pony appearing on the show.  Only for the outcome parts, the text is either colored green or red, depending on the outcomes.

Twilight Sparkle

Season 1 Had to appear in every episode in order to write friendship reports to Princess Celestia.
Season 2 Was given absences this season upon allowing her friends to write the reports. 
Season 3 Same as in Season 2.
Season 4 Still had as much major roles as in previous seasons.
Season 5 Same as in Season 4.
Season 6 Upon having Starlight Glimmer take her place this season, had no solo episodes for the first time.
Season 7 Got at least 4 major roles this season.
Season 8 For now: For a second season in a row, is consuming most of the appearance time.


Season 1 Had the most major roles of the Mane Six, was absent in only two episodes, and had at least one cameo.
Season 2 Only got two major roles and more absences in order to allow the other ponies more screen time.
Season 3 Appeared in every episode but had no major roles. Still, quite an unfair season for Rarity.
Season 4 Had more screen time than in the previous two seasons, but also even more absences (5).
Season 5 Had her only three major roles in a row halfway through this season. Other than that, also had pretty bad luck in the first half of this season and late this season as well.
Season 6 Was needed to appear a lot this season to make up for all that bad luck from Season 5.
Season 7 Did very well, though not as well as Starlight Glimmer.
Season 8 For now: Is in last place in screentime, but not that far behind.


Season 1 Appeared in all episodes except one.
Season 2 Had three absences, again all within the second half of this season, when by then, she was in for bad luck with not enough major roles.
Season 3 Appeared in all episodes.
Season 4 Only absent twice.
Season 5 For the first time, had much less appearances in the first half of the season than in the second. Talk about bad luck!
Season 6 Same as in Season 5, but with some better luck than in that season.
Season 7 Did not do so well this season, having gotten the least screentime.
Season 8 For now: Likely to get very little screentime for a second season in a row.

Rainbow Dash

Season 1 Between the entire Mane Six, had the worst luck with no solo episodes (as Sonic Rainboom was also a Rarity episode).
Season 2 Did fine, but still needed a little more screen time after two seasons.
Season 3 Appeared in every episode, which was somewhat better luck.
Season 4 Had more better luck there.
Season 5 Again, had pretty bad luck like in the first two seasons, with only one solo episode and setting a new record of the smallest number of appearances in one season.
Season 6 Like Rarity, had to appear more this season than in the previous one to make up for all the bad luck (though this didn't happen until about halfway into the season).
Season 7 Started off very low but caught up in later episodes and ended up in next to last place (in screentime).
Season 8 For now: Is flaunting the rest of the Remane Five, and still getting more episodes later this season.

Pinkie Pie

Season 1 Did fine this season, but had not as much appearance time as Fluttershy did. Not very good luck there.
Season 2 Had very good luck this season, with plenty of appearance time (mostly in the second half) and no non-speaking appearances, cameos included.
Season 3 Had to lose one episode because of her excellent performance so far in the show.
Season 4 Tied with Season 1 for the biggest number of appearances, but had the least screen time this season. Bad luck, I must say.
Season 5 Did even better than Rainbow Dash and Rarity this season, even with three absences in a row. Plus, also had more dialogue than Applejack.
Season 6 Set another new record for smallest number of appearances in one season in addition to needing more episodes with other characters that there wasn't any room left for solo episodes. What tough luck!
Season 7 Did very well this season, mainly due to within the first half.
Season 8 For now: For the first time in many seasons, has appeared less than Spike, but not too far.


Season 1 Did pretty well this season, with at least four major roles (three from the second half).
Season 2 Not too bad luck, but lost an episode because she just used up her major role with the Cutie Mark Crusaders in Season 1.
Season 3 Did barely better than Rarity, with one major role (though it wasn't quite a solo episode).
Season 4 Did fine, with the same number of appearances as Rarity this season, but with less screen time.
Season 5 Far more bad luck than in previous seasons, but at least had three major roles (including one of the Discord episodes of this season).
Season 6 Bad luck continues with even less appearances than in Season 5.
Season 7 Unlike in the last two seasons, actually did a little better.
Season 8 For now: Again, might get very little appearance time in one season.