Red Moon
Channel the power of the enraged moon to deal (640% of Spell Power) Arcane damage to your target over 8 sec. Casting Mangle extends its duration by 1.1 sec and generates 8 Rage.
Tree position
In the Guardian Druid talent tree, Red Moon sits in the Guardian specialization talents, row 9 of 14. It is a single-point node. Its row opens once 20 points are spent in Guardian Talents.
Choice node
Red Moon shares its node with Twin Moonfire. A character takes one of the two.
Twin MoonfireMoonfire deals 8% increased damage and also hits another nearby enemy within 15 yds of the target.
Connected above
The tree draws a line into Red Moon from Ursol's Warding and Lunar Beam.
Ursol's WardingGain magical damage reduction equal to 10% of your damage reduction from armor.
Lunar BeamSummons a beam of lunar light at your target's location, dealing (40% of Attack Power) Arcane damage each second to your target and (40% of Attack Power) to up to 5 other enemies within yd. Lunar Beam also increases your mastery, and heals you over 8 sec.
Connected below
Red Moon leads on to Elune's Favored and Galactic Guardian.
Elune's FavoredWhile in Bear Form, you are healed for 18% of all Arcane damage done.
Galactic GuardianYour damage has a 5% chance to trigger a free automatic Moonfire on that target. : When this occurs, the next Moonfire you cast generates 8 Rage, and deals 300% increased direct damage. : When this occurs, you gain 1 charges of Lunar Wrath. Each 20 Rage you spend while Red Moon is active consumes a stack to deal (100% of Spell Power) additional Arcane damage to its target and heal you for (130% of Spell Power).
Same row
Also on this row: Ursoc's Fury, Flashing Claws, Blood Frenzy, Moonless Night and Fury of Nature.
Ursoc's FuryThrash and Maul grant you an absorb shield for 35% of the damage dealt for 15 sec.
Flashing Claws2 ranksThrash has a 10% chance to trigger an additional Thrash. Thrash stacks 1 additional times.
Blood FrenzyThrash also generates 3 Rage each time it deals damage, on up to 5 targets.
Moonless NightYour direct damage melee abilities against enemies afflicted by Moonfire cause them to burn for an additional 20% Arcane damage.

Talent trees
Red Moon is in the talent tree of 4 specializations. Druid: Balance (DPS), Feral (DPS), Guardian (Tank), Restoration (Healer).
Red Moon Changes by patch
Tracked changes to this talent between game data builds, newest first.
- First tracked in the game data (patch 12.1.0)