An Effriti Ghost
He followed the party, harassing them until he confronted Feng. He spoke of a broken prophecy and declared a desire to take Feng’s body. The Party fought him, but the battle ultimately came down to a battle of wills between him and Feng. He lost. It is possible he has been defeated, but one can never be certain with the undead.
His explosive magic left behind glassed sand and rings of six rubies, possibly from the Ruby Mountain. This magic is similar to that which was encountered shortly after first meeting Cressida Shesel; it is unknown if this is a signature feature of his magic or simply the result of the style of magic he used.