Achievements on all dates: Steam 

This was my first "gather achievements on all dates" goal as I finished this all the way back in 2017. Video released on the exact time my Steam account turns 10 (i.e. 1 August 2024 at 10:43 local time).
UAHR (Unified Achievement Hunting Rules): achievementhun...
Completionist calendar: completionist.... (need to have an account though)
Completionist: completionist.... (doesn't need account but you need to find the dates/achievements yourself; page 1-11).
Music: "Spirit of Fire" by Jesse Gallagher