Mastery is the operator-skill system Morefun added in Season 6: White Nights. It is small on purpose: twelve points, earned by account level, spent on modest improvements to basic skills, reallocated whenever you like. If you came here for a "best Mastery build" list — read the last section first, because we are not going to invent one.
The rules, from the Season 6 announcement
- 6 points by default. Every operator gets them on day one of the season.
- 6 more by level 26. Character level, not anything you buy.
- 12 is the cap, for everyone. Morefun: "max-level players will automatically start the new season with 12 Mastery Points, which is also the cap, requiring no extra investment or consumption." The cap is not raised by seasons played, Bonds, or the battle pass.
- Free reallocation. The dev talk bills it as "flexible respecs to suit different tactical needs"; the announcement says operators "can freely adjust their Mastery Point allocation."
- "No superpowers." The studio wrote that line into the feature list themselves, in response to what they called "the community's concerns and worries about extra abilities for operators." Mastery enhances basic character skills — the kind of thing you would expect from a fitter operator — rather than adding abilities.
That last point is the one worth understanding before you compare the game to anything with hero kits. The Distorted Valley mode in Season 5 had "ability perks" chosen before a raid; Mastery is the permanent, account-wide version of the idea with the power level turned down.
Where it matters most
Morefun's own guidance in the 3 July update pointed Hostile Sector players at it: "don't forget to make good use of the Mastery System to build a setup that suits you." The PvE modes are where a survivability-leaning spread pays off, because you are fighting reinforced AI for long stretches rather than one squad fight. For normal raids the trade-offs are the usual ones — whatever helps you carry more or move better against whatever helps you win the first exchange.
Season 7 adds a second, separate progression line: Zombie Research spends points earned in Infected Zone on perks that are specific to the zombie modes. That is not Mastery; the Season 7 page has the announcement text.
What we will not tell you (yet)
The per-node values. The Mastery screen in the client lists every node and its effect, and the game data we extracted does not include those numbers in a form we can verify against the live build — the client stores them encrypted, and we do not publish figures we cannot check. When the community wiki documents the tree with sourced values, or Morefun publishes it, this page gets a full table and a "best for" section built on it. Until then, any site ranking "best Mastery points" without listing the values is telling you what its author likes.
What you can do now: open the tree in-game, note the twelve-point budget, and pick for the mode you play most — you can re-spread them for free before the next raid. The beginner guides cover the rest of the early progression, and the ranking system guide covers the other thing your level unlocks.