Putative transcription factor that may potentiate the function of warA. Developmentally regulated and preferentially expressed starting at the mound stage in response to cAMP. Expression seems to require the transcription factor gbfA. No visible phenotype. Hbx2 and warA double mutants form fruiting bodies with an enlarged basal disk and lower portion of the stalk and the anterior of slugs is not as cylindrical as that of wild-type slugs.