Unlock Diablo Beta:
     Go  to  the  Config menu and select Voice. Play these in order to
unlock Diablo Beta for purchase:
89, 17, 8, 29, 31, 58, 93 and 81. 

Unlock Cyclops:
     Go  to  the  Config menu and select Voice. Play these in order to
unlock Cyclops for purchase:
5, 60, 66, 60, 11, 60, 25, 60 and 60. 

Unlock Cyclops Type-1:
     Go  to  the  Config menu and select Voice. Play these in order to
unlock Cyclops Type-1 for purchase:
3, 39, 74, 21, 28, 43, 79, 82, 91, 61, 69, 32, 96, 25, 4, 66 and 49. 

Unlock Diablo Tiger:
     Go  to  the  Config menu and select Voice. Play these in order to
unlock Diablo Tiger for purchase:
2, 37, 2, 36, 2, 38 and 2.