| Artist name | Roles | Recordings |
|---|---|---|
| Coro del Teatro dell'Opera di Parma | ||
| Stephan Oster (cellist) | ||
| 4th Disciple | producer | Showdown |
| Artist name | Roles | Recordings |
|---|---|---|
| Coro del Teatro dell'Opera di Parma | ||
| Stephan Oster (cellist) | ||
| 4th Disciple | producer | Showdown |
| Artist name | Roles | Recordings |
|---|---|---|
| 4th Disciple | producer | Showdown |
| Artist name | Roles | Recordings |
|---|---|---|
| Coro del Teatro dell'Opera di Parma | vocal | Nightmare in A-Minor |
| Stephan Oster | performer | Can't Loose |