Group 14 compounds in the zero-oxidation state, L→E←L (L = a two-electron donor), were discovered only a decade ago. 1-3 These compounds are cumulatively called tetrylones and are now known for all tetreles. They possess two lone pairs centered on the group 14 element and exhibit nucleophilic properties.4,5 We have recently succeeded in preparing a new germylone compound 1 supported by a diimino-carbene pincer (dimNHC), which exhibits ambiphilic reactivity in the oxidative addition of HCl, MeI, PhI and oxidative cyclization with a quinone.6 Interestingly, the oxidative addition reactions are accompanied by the little known migration of the R group from germanium to the NHC ligand to afford halo-alkyl germylenes. Further development of this chemistry will be also discussed. 7,8