Phi Mu
Mu Sigma Beta
Beta Theta Pi
Pi Kappa Alpha
Alpha Gamma Delta
Delta Delta Delta
Delta Sigma Phi
Phi Delta Theta
Theta Chi
Chi Phi
Phi Sigma Kappa
Kappa Kappa Gamma
Gamma Phi Beta
Beta Sigma Psi
Psi Upsilon
Ok, so I repeated a letter like once or twice, but it was hard, this is as far as I got.
Fun topic!