I'm sure there's others I'm not remembering, but let me make a list of the highlights as far as I can recall..
Dark Patch is a very influencial card for Expanded. It returns Yveltal to the amazing speed that it had last year. Coupled with Battle Compressor, this can make turn one Evil Balls very likely, allowing you to hit for massive damage in the early game. Despite M-Manectric hampering the deck's ubiquitous nature of the past, I can see a lot of people playing it in Expanded. Shadow Circle can also negate this weakness to an extent (it's not too hard for the opponent to play a different Stadium). This deck can also benefit from the return of Sableye DEX, which can recover Item cards and let them be used again.
Level and Heavy Ball also return, and were played in many decks in the past format. You can expect Metal decks to run a lot of Level Balls for pulling out Bronzor / Bronzong with else, as well as Aromatisse, Pyroar, or anything that plays Jirachi-EX.
The infamous Tropical Beach is playable in Expanded, but the pool of decks that rely heavily on it has decreased drastically. Stage 2s in general are not viable due to the prevelance of Seismitoad. Item lock hurts these too much. Still, the Beach could be seen in decks like Metal, Eels (see below), even Donphan for early game draw power.
Eelektrik NVI (Eels) proved to not be strong enough to win big at Regionals. However, the similar Metal deck seems pretty reliable, and with help from Battle Compress and VS Seeker, this deck could have what it takes (maybe). Time will tell.
Skyarrow Bridge gives free retreat to pretty much everything that's run in a Virizion/ Genesect deck. This card was definitely key to VirGen's massive success at Worlds, as well as the Expanded portion of fall Regionals.
Prism and Blend energies are helpful in both Aromatisse (well, not Blend for this) and Plasma decks, and contribute to their high versatility. In Aromatisse especially, having eight "wild card" energies in your deck makes it a lot more feasible to run non-Fairy attackers and not worry about Enhanced Hammer.