I really liked this core, Kyurem-B and Diggersby form a stupidly strong wallbreaking duo to smash through most things, but they are both fairly slow and struggle vs offence. Focus sash on Diggersby increases chances to set up a swords dance and lets you revenge CharY. Rather than just slap on a scarf to remedy the speed issue, I added Skarmory to bring tailwind support, which makes both incredibly fast - Kyurem-B in particular outspeeds pretty much everything including scarfers and allowing it to run band instead to absolutely wreck face especially once fairies and steels have been removed (Diggersby's earthquake helps with this). Custap Berry means I can get off a free clutch tailwind turning a bad situation on its head (thanks
slurmz). Skarmory also brings stealth rock, steel dragon and fairy resists, and checks key threats to the core such as M-Medi, M-Lop, Weavile, etc. Starmie was next, spin support is obvious but it also brings more reliable speed if I can't get a tailwind up, valuable fire ice and fighting resists to check the likes of Victini and Keldeo, recover to better check aforementioned mons, also absorbs will-o-wisp and scalds with natural cure which is vital for this team. CB Azu serves as a Talonflame, Bisharp, M-Sab etc check with its typing and power, more priority to increase the matchup vs offence and also benefits greatly from Skarmory's tailwind, Superpower to lure steels such as Ferrothorn for Kyurem-B. Finally, specially-bulky M-Zor brings me another potential wincon with SD. Special defence complements Skarmory's physical bulk, more priority = bonus, a psychic check, pivot, and a better Weavile and fairy check to allow Kyurem-B to more freely spam CB-boosted outrage. Team is kinda weak to CharY if rocks or tailwind aren't up though since 3 members can outspeed/out-prioritise and do over 50% it usually only gets one kill a game, Diggersby also wins if focus sash is intact, Skarm can also set up a tailwind if at full health or in custap range.
Overall the team has a great offensive and defensive synergy to support each other in taking on each other's threats, a huge amount of power to break through defensive teams, tailwind and multiple priority users to smack offensive teams, and multiple potential wincons in any given match - pretty much every mon bar Skarmory can wallbreak early game or potentially sweep mid/late game, given the right circumstances, which the other teammates provide.