A quick beam of lunar light burns the enemy for (20% of Spell power) Arcane damage and then an additional (104.4% of Spell power) Arcane damage over 12 sec.
Balance (Level 10) Generates 2 Astral Power.
Rank 2 (Level 14) Duration increased by 4 sec.
Rank 3 (Level 33) Moonfire and Sunfire duration increased by 6 sec.
A quick beam of lunar light burns the enemy for (15% of Attack power) Arcane damage and then an additional (120% of Attack power) Arcane damage over 16 sec.
It's often considered an excellent choice for pulling, regardless of the druid's specialization due to its instant cast and long lasting DoT.
If an enemy is at low health you can finish them off by spamming several Moonfire or [Sunfire] in a row. This is low DPS, but can be done on the move to a fleeing enemy.
Trivia
Moonfire is a basic Druid spell in Hearthstone. The flavor text reads: ""Cast Moonfire, and never stop." - How to Be a Druid, Chapter 5, Section 3"
Now has a base duration of 20 seconds (up from 14 seconds), but is no longer extended by [Starfire] and [Starsurge] critical strikes. Upon reaching 100 Lunar Energy, the next Moonfire deals 100% additional initial damage.
Moonfire and Sunfire will now replace each other on the Action Bar when switching cycles on the Eclipse Bar.
Patch 5.0.4(2012-08-28): No longer generates any Energy or changes into Sunfire while in Solar Eclipse.
Hotfix (2011-07-19): "Moonfire will now generate Lunar Energy when crossing from Solar to Lunar on the Eclipse bar."
Patch 4.0.6(2011-02-08): Now costs 9% of base mana, down from 18% of base mana.