Cheats tested!
Thanks very much, Martin! After looking at your cheats I finally got the idea. Here are some more I found. First, the "boss" cheats work only for the giant, not for the boss devil or boss "Satan". So after some work I got to find and check cheats for all sets. I must add that 3 x stronger is too much hard, I think twice is enough to give some hard time to experienced players! The "Gargula" is that character with a heart tattoo in his arm from 2nd stage.
Altough included here, I'm still to find the "Boss Satan" cheats (0000 address), ran out of patience for now.
gng:0:EFCF:00

Always kill Boss/Devil with 1 Shot
gng:0:B737:09

Devil = 6 shots (harder!)
gng:0:CF5F:14

Gargula = 20 shots (harder!)
gng:0:C554:14

Boss Giant = 20 shots (harder!)
gng:0:BEF2:14

Boss Devil = 20 shots (harder!)
gng:0:0000:14

Boss Satan = 20 shots (harder!)
gnga:0:EEFC:00

Always kill Boss/Devil with 1 Shot
gnga:0:B5AA:06

Devil = 6 shots (harder!)
gnga:0:CE48:14

Gargula = 20 shots (harder!)
gnga:0:C404:14

Boss Giant = 20 shots (harder!)
gnga:0:BDCB:14

Boss Devil = 20 shots (harder!)
gnga:0:0000:14

Boss Satan = 20 shots (harder!)
gngt:0:EFEF:00

Always kill Boss/Devil with 1 Shot
gngt:0:B747:06

Devil = 6 shots (harder!)
gngt:0:CF6F:14

Gargula = 20 shots (harder!)
gngt:0:C564:14

Boss Giant = 20 shots (harder!)
gngt:0:BF02:14

Boss Devil = 20 shots (harder!)
gngt:0:0000:14

Boss Satan = 20 shots (harder!)
makaimuc:0:EF14:00

Always kill Boss/Devil with 1 Shot
makaimuc:0:B5AB:06

Devil = 6 shots (harder!)
makaimuc:0:CE4C:14

Gargula = 20 shots (harder!)
makaimuc:0:C3FD:14

Boss Giant = 20 shots (harder!)
makaimuc:0:BDCB:14

Boss Devil = 20 shots (harder!)
makaimuc:0:0000:14

Boss Satan = 20 shots (harder!)
makaimug:0:EF2B:00

Always kill Boss/Devil with 1 Shot
makaimug:0:B5B1:06

Devil = 6 shots (harder!)
makaimug:0:CE5B:14

Gargula = 20 shots (harder!)
makaimug:0:C407:14

Boss Giant = 20 shots (harder!)
makaimug:0:BDD2:14

Boss Devil = 20 shots (harder!)
makaimug:0:0000:14

Boss Satan = 20 shots (harder!)
makaimur:0:EF1F:00

Always kill Boss/Devil with 1 Shot
makaimur:0:B5A5:06

Devil = 6 shots (harder!)
makaimur:0:CE4F:14

Gargula = 20 shots (harder!)
makaimur:0:C3FB:14

Boss Giant = 20 shots (harder!)
makaimur:0:BDC6:14

Boss Devil = 20 shots (harder!)
makaimur:0:0000:14

Boss Satan = 20 shots (harder!)
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