Cheat mode:
Load or reset the game, then execute the following BASIC command before running or restarting the program. 

POKE 27018,169
POKE 26121,90
POKE 26122,125
SYS 2512 
Unlimited lives:
Load or reset the game, then execute the following BASIC command before running or restarting the program. 

POKE 25117,173
SYS 24576 
Level select:
Load or reset the game, then execute the following BASIC commands before running or restarting the program. Note: X equals a level number from 0 through 3. 

POKE 24969,X
POKE 24576
SYS 24576 
Invincibility:
Load or reset the game, then execute the following BASIC command before running or restarting the program. 

POKE 27015,10
SYS 24576 
Invincibility (alternate):
Load or reset the game, then execute the following BASIC command before running or restarting the program. 

POKE 27018,169
SYS 24576 
Full weapons:
Load or reset the game, then execute the following BASIC command before running or restarting the program. 

POKE 25076,2
POKE 25306,2
SYS 24576 
Orbs:
Load or reset the game, then execute the following BASIC command before running or restarting the program. Then, press Q for Orbs. 

POKE 25122,90
POKE 26122,125
POKE 26163,165