It's not super old but I patiently waited for a sale on the Repentence DLC for The Binding of Isaac. Besides the new content it's also a sort of v2.5 of the game (if Rebirth/Afterbirth was v2.0) with many quality of life changes. Admittedly some of the changes were a bit startling at first but I quickly got used to them and after a few hours it felt like home again.
I have about 500 hours in Isaac and this refresher has breathed new life into it so perhaps I am good for another 500.