The Pit, Barbican, LondonElisabeth Gunawan's mythological horror blends puppetry, dance, theatre and film to explore the effects of a family's relocation from Hong Kong to the US Like so many mythic creatures, the hungry ghosts of Buddhist and Chinese traditions " ghouls with huge stomachs and small mouths, tormented by their own insatiable appetites " is a fecund figure, giving rise to all sorts of stories and meani…