I felt like making a thread for this! In this thread, please post and discuss strong cores in the ADV NU Metagame.
I'll start off with a couple.
Sableye+Flareon
A very solid defensive core, covering large amounts of threats, and very difficult to break.
Huntail+Rain Dance Plusle
Rain Dance on Plusle allows it to use fully accurate Thunders, and can Baton Pass to Huntail, letting it sweep without having to set up its own Rain.
SDpass Mawile+Silk Scarf Pidgeot+CB Diglett
SDpass Mawile enjoys being paired with Silk Scarf Pidgeot, since it can abuse Mawile's Ground weakness as an easy opportunity to come in. Diglett comes in easily when Baton Passed into by Mawile, whilst it's able to capture Rock and Steel types that prevent Pidgeot from sweeping.
I'll start off with a couple.
Sableye+Flareon


A very solid defensive core, covering large amounts of threats, and very difficult to break.
Huntail+Rain Dance Plusle


Rain Dance on Plusle allows it to use fully accurate Thunders, and can Baton Pass to Huntail, letting it sweep without having to set up its own Rain.
SDpass Mawile+Silk Scarf Pidgeot+CB Diglett



SDpass Mawile enjoys being paired with Silk Scarf Pidgeot, since it can abuse Mawile's Ground weakness as an easy opportunity to come in. Diglett comes in easily when Baton Passed into by Mawile, whilst it's able to capture Rock and Steel types that prevent Pidgeot from sweeping.