Green’s Dictionary of Slang

(S.Afr.) an exhortation, esp. in the context of sports events or business meetings when the subject(s) of the cry has to pull something special out of the hat.

1983		P.–D. Uys Farce about Uys 77: evita: Gee my die goed! (He doesn’t and she turns to Sophie for more) Vat hom, Fluffie!
2002		summary of ‘Oom Schalk Strikes Back’ www.wordsandpictures.co.za 🌐 But, ultimately, Oom Schalk is ‘really Shakespearian in his style’, and so ensues a duel whereby ‘Cry havoc let slip the dogs of war’ becomes ‘vat hom fluffie.’.
2006		southafricanrugby.blogspot.com 16 July [blog] Vat hom Fluffie or whatever is said in the changing rooms to talk up a team we need it.