How to Obtain:
This shirt is owned by Ghetz, Greco's friend. Ghetz's Shirt cannot be obtained except through a Gameshark code. It's dropped by an unused Wraith that can't be found in-game. Since the Wraith in question follows monster #104 (Gloop in Viper Manor sewers), the Wraith was probably going to be the one near the hole close to the forest exit; it's likely developers simply forgot to add it or mistakenly put a normal Wraith there.
A Brady Game guide listed the unused monster, sparking several rumors that a Wraith drops the shirt in the Hydra Marshes; these often involve elaborate plots and requirements to receive the shirt.
A patterned shirt with really bad taste!
The genesis of the Ghetz rumors; thanks to V_Translanka
Probably the Wraith intended to be the Ghetz's shirt Wraith
From: Armor (Chrono Cross)