I saw this NPC cast two spells while we were fighting it:
[Sun Jul 04 02:23:16 2010] A Resonating Crystalkin begins to cast a spell. <Song of My Beauty>
[Sun Jul 04 02:23:19 2010] A Resonating Crystalkin begins to cast a spell. <Resonant Hum>
Resonant Hum seems to be the drunkenness-and-melee-effects spell mentioned by others below, while Song of My Beauty appears to be a Directional AE nuke, as well as a Knockback effect.
Rondor