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We’re gonna miss Dancing With the Stars somethin’ awful after tonight’s big Season 18 Finale!

There’s a lot of entertainment on tap for the final show of the spring 2014 season — including performances from Season 17 champion Amber Riley, Christina Perri, Iggy Azalea, and Ariana Grande — but the work is not yet done for our intrepid final three.

Candace Cameron Bure and Mark Ballas, Meryl Davis and Maksim Chmerkovskiy, and Amy Purdy and Derek Hough have one last competitive routine: the 24-Hour Fusion Challenge.

The couples have to fuse two contrasting dance styles that they’ve performed this season, with less than 24 hours to prepare the dance for judges’ points. As Amy Purdy tweeted last night, after the Finals, "Wowza, from the live show straight to the dance studio we have just a few hours to learn a new dance. Nuts!"

They did this last year, too, and Karina Smirnoff said "24-Hour” challenge was a misleading title because they only really had eight to 10 hours, depending on how long you could stay awake. She and Corbin Bleu performed a Cha-Cha Foxtrot that got three 9s. Amber Riley and Derek danced a Samba Quickstep that got a perfect score and may have helped seal their victory. So you never know, these could be the real make-or-break routines, even more than last night's Freestyles.

Which 24-Hour Fusion routine are you most looking forward to seeing tonight? Do you think the scores will affect the outcome, or have the champions already been decided, back on last night’s dances, scores, and votes?

The DWTS Season 18 Finale airs Tuesday, May 20 from 9 to 11 p.m. ET on ABC.