The phrase "interesting gimmick" refers to a unique or clever feature or idea that grabs people's attention or adds novelty to something. Full definition
Mario and Luigi Bowser's Insiade Story applied a new, and very interesting gimmick of helping Bowser from the inside. (mariopartylegacy.com)
This is a rather interesting gimmick, although I do have to say it makes this fight one of the most annoying in the entire game since the Chomp's movement is slow and unpredictable and Iggy actually fires magic at you while moving unlike the rest of his siblings. (gamingreinvented.com)
That's an interesting gimmick, breaking down to a dollar for every year (by Lazio's calculation) the AG has been in Albany. (nystateofpolitics.com)