The Mana Reservation Efficiency mastery has been replaced as there is now a much larger amount of Mana Reservation Efficiency for Curse Auras on the passive tree." (The mastery was 30%) :
Empower Support PoE Leveling Fast, Max Level 4, 5, Drop, Farming 3.22
Bug Reports - Determination Mana Reservation Mastery and Blood Magic - Forum - Path of Exile
This New Cluster Will Help You Get Stun Avoidance More Easily In POE 3.21!
Passive Skill Tree Guide for Beginners - Path of Exile - Maxroll.gg
Mana reservation bug with Hierophant's "Sanctuary of Thought" node · Issue #1655 · Openarl/PathOfBuilding · GitHub
Reservation - Path of Exile Wiki
Passive Skill Tree Guide for Beginners - Path of Exile - Maxroll.gg