@Liechi Berry/Salac Berry
BU Passing is rarely done this days, and Floatzel is still one of the more reliable ways of doing it, thanks to his speed and immunity to burns, while Toxic gives him something to screw Alomomola and Ludicolo over. The most interesting option is to use a pinch berry - if Floatzel gets off a single BU, he's either passing on +2 Atk/+1 Def, or +1 Atk/Def/Speed, and if you get off more than one Bulk Up it's even better. I like to use him with Liechi SmashCarracosta, but other possible options are Pokemon that appreciate the ability to forego a boost and hit hard right off the bat or to make them even stronger. Floatzel has the option to run AgilityLiechi, AgilitySalac or even BulkUpPetaya for mixed sweepers, but the former are generally outclassed by Ninjask.