At the password screen:

Password - Effect

UKCGNNKT - Level 8 Stage 1
UAGRQQNE - Level 8 Stage 2
UAGRQJNA - Level 8 Stage 3
UANRQINE - Level 8 Stage 4
MUGWNGPC - Level 8 Stage 5
UKRGNTKV - Level 8 Stage 6
UAGRBINA - Level 8 Stage 7
UANRQQNZ - Level 8 Stage 8