Iriomote, Japan
In contrast to the Varied Tit, the nigriloris race of Great/Japanese Tit endemic to Ishigaki and Iriomote is quite distinct in both plumage features and vocalisations, and should deserve more attention as the whole Great/Japanese/Cinereous Tit complex is still subject to taxonomic investigation (as i wrote this i just realised that HBW is actually relumping them into one species, no less...). Slaty grey above with little/no white at the edge of the coverts, dusky grey under, having more extensive black on the cap, nape, bib and belly leaving only a small white cheek patch, a very thick bill, it certainly looks different from your friendly neighbourhood Great Tit, and it has vocalisations i never heard from any other races of the complex. The bird is quite common on both Ishigaki and Iriomote, clearly adapting well to disturbed habitat.
Japanese/Great "Ishigaki" Tit (ssp nigriloris)