Constant fights:
Highlight the "Fighting" selection at the options 
screen. Then, hold L and press C-Right, C-Left(2), 
C-Right, C-Down, C-Up(2), C-Down, C-Left, 
C-Right(2), C-Left, C-Right, C-Left. A line of 
numbers will appear to confirm correct code entry. 
A fight will break out at regular intervals during 
the current period. 

Change player appearance: 
Press C-Down + R, C-Left + R or C-Up + R at the 
options screen. Modify the first six bits of a 16-bit 
register to change the game be pressing: 

C-Down + R (head size, alters bits 1 and 2)
C-Left + R (body size, alters bits 3 and 4)
C-Up + R (announcer's voice, alters bits 5 and 6) 

Register Effect 
100000 Stocky Players. 
010000 Stocky Players, Big Heads. 
110000 Stocky Players, Small Heads. 
001000 Small Players, Small Announcer. 
000100 Large Players, Large Announcer. 
000010 Crunched Players, Small Announcer. 
000001 Elongated Players, Large Announcer. 
110110 Large Players, Small Heads, Large Announcer 
010010 Crunched Players, Large Heads, Small Announcer 
010101 Large Players, Large Heads, Large Announcer 
010001 Elongated Players, Large Heads, Large Announcer