Paragon Levels is a XP-driven progression system for your characters after hitting the game's level cap.
The Paragon levels return from Diablo III with a twist: in Diablo Immortal, there are ten Paragon Talent Trees that each offer unique bonuses both in the form of stat boosts and distinct perks. The four trees currently in the Alpha are:
Talents in this tree greatly enhance your survivability when fighting monsters.
This tree enhances your XP gains and increases your chances of finding treasure, gold, and gems.
If you’re looking for talents that make you more lethal when fighting monsters, look no further.
Talents in this tree greatly enhance your effectiveness when fighting other players.
You earn Paragon Points simply by gaining XP once you hit the level cap. You can spend these points across all the Paragon trees you have unlocked, so you could, for instance, spend one point in the Survivor tree, then the next point in the Vanquisher tree, and so on. However, while diversification is useful and even something encouraged, there is a catch: only one tree can be set to active at any time.
What that means is that each Paragon tree offers Permanent Attributes and Specialization Skills. Permanent Attributes are stat boosts you get continually from points spent. Specialization Skills only benefit you when you choose to activate their Paragon tree. If you change which Paragon tree is active, you get access to a different group of Specialization Skills, but the Permanent Attributes always remain.
For example, Vanquisher has a Passive talent that increases your Offense Rating and an Active talent called Zeal that increases your attack speed after killing monsters. If you deactivate Vanquisher and activate a different Paragon tree, Zeal will no longer function, but your Passive Offense Rating will remain.