@ccmatta dont b scared friend, tell your story

Yep two sounds manageable and true lots of opportunity for exploration
Thats a cool idea telling bits about them so readers get accustomed and would eventually want to know more about them.
For mines-
In season 1 the main cast is small 3 main (two brothers and their mentor) and about five reoccuring.
(Season modelled after TV series 20-22 episodes & each tapas episode being 1/5 TV Episode)
The cast grows in later seasons:
Season 2 - 4 the hero cast evolves into a team dynamic of 6 characters like Ninja Turtles, Power Rangers & Voltron.
While the 2 brothers remain major throughout, some of the others that make up the total 6 get swapped in the different seasons.
And if you include the obstacle/antagonist per season, the main cast is about 7-9.
I won't go through lengths exploring each chara backstory, but use their actions, character design and personal belongings to give the reader clues. So viewers can make up their own theories of some background characters too.
Outside the focussed cast, the story is a Battle Royale taking place so the human cast across 4 seasons is large, about 50. For story relevancy most are minor and BG characters to be fodder for the high stakes of narrative, many die by the numbers.