Return is a great option on Offensive Dragon Dance as it hits everything Gyarados needs to hit for neutral damage. You can hit Rotom-W, Celebi, Dragon-types, and Keldeo (there are more stuff but I'm on the phone) even harder than Stone Edge / Earthquake can. Imo, it should get a slash or at least an AC mention.
Also Return is legal with Moxie and using Double-Ege with LO is suicidal at best, especially considering that Gyarados is weak to Stealth Rock and does not set up so easily.
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