Credit: ABC

We doubted that anything could top tonight’s epic episode of Once Upon a Time (Season 2, Episode 21: “Second Star to the Right”), but from the looks of next week’s promo, the second installment of the two-part finale is going to be even more epic.

Last we left our Storybrooke residents, Greg Mendell and Tamara were on the loose with Regina’s fail-safe black diamond (which can obliterate the town in one fell swoop), and Regina was on the road to recovery after being kidnapped and electrocuted by the aforementioned evil magic haters.

In the promo, we see them in cohorts with Captain Hook again, and he’s not afraid to question them. “You're willing to destroy an entire town and kill everyone on it?” he asks, to which Greg says, “We're willing to die for our cause.” They proceed to throw the diamond in the mines and watch as its effects take over Storybrooke.

However, with evil comes good — or at least the two forces joining together to save the town. The Charmings and Emma are seen with Regina, who works hard to make sure everyone won’t die. “There is no stopping it. The best thing I can do is slow it down,” she says, and we see her channeling all of her magic into the diamond in the mines.

The fate of the fairy tale character-filled town doesn’t look good, though. We see Rumplestiltskin and Belle (erm, Lacey) crying, The Charmings and Emma holding each other, and everyone running frantically. And as black, tentacle-like clouds swirl around the clock tower and Regina says, “I can't contain this much longer,” we officially got nervous.

Check out the promo below, and then you tell us: Do you think Storybrooke will be destroyed in the finale? Sound off in the comments!

The Season 2 finale of Once Upon a Time airs Sunday, May 12, 2013 at 8 p.m. ET on ABC.

Alyse Whitney is an editor at Wetpaint Entertainment. Follow her on Twitter @AlyseWhitney.