In the ‘00s, The Matrix were the go-to gurus for artists who wanted to add pop panache to their music, with nu-metal stalwarts Korn and indie queen Liz Phair among those seeking their wisdom. Peppy cuts like Avril Lavigne's “Sk8er Boi” and sweeping ballads like Britney Spears' “Shadow” showcase the trio's knack for penning and producing hooky tracks that amplified their artists' personalities.