  We present an analysis and re-appraisal of the massive, carbon-enriched (DQ)
white dwarf (WD) LP 93-21. Its high mass (~1 M_sun) and membership to the class
of warm DQ WDs, combined with its peculiar halo kinematics suggest that this
object is the product of an ancient stellar merger event, most likely that of
two WDs. Furthermore, the kinematics places this object on a highly retrograde
orbit driven by the accretion of a dwarf galaxy onto the Milky Way that
occurred at a red shift greater than 1.5. As the product of a stellar merger LP
93-21 is probably representative of the whole class of warm/hot DQ WDs.
