變鬼變怪 [变－变－]

Jyutping bin3 gwai2 bin3 gwaai3
Pinyin biàn guǐ biàn guài

Definitions (Wiktionary)
  1. noun, Min-Nan
    to play tricks; to be up to some mischief; to use trickery
    (syn.) 变鬼, 變鬼