Looking to level Brann before the release of Season 1? The first Delve completed each day rewards bonus experience for Brann!
For the first Delve of the day, players will get rewarded with a Purple-rarity Companion Experience which drops a significantly higher amount of experience than a typical Delve completion.
In personal testing, a Tier 3 Delve awarded 4410 Companion Experience. Brann required a total of 15000 Companion Experience to gain a level so this covers just shy of a third of the total experience needed.
As Brann levels, he gains a variety of useful talents and passives that can aid players. As a DPS, he can earn the ability to interrupt, stun, buff player damage, etc. As a Healer, Brann can learn how to dispell, give players a Damage Reduction, etc.
Furthermore, Brann has an endgame talent depending on his role that can be very beneficial once higher Tier Delves get released: Explorer's Medical Journal/Explorer's Ammunition Journal. This gives Brann a 5% Damage or Healing buff depending on his role starting at Rank 1 and going all the way up to Rank 50. Meaning at Rank 50, Brann can earn a whopping 250% increase to his Healing or Damage. Once Season 1 releases and Zekvir's Lair is available, this will be extremely helpful for players looking to earn the Solo achievement: Let Me Solo Him.