Castlequest

SXKAVIVG        Infinite lives 
ATSXATEY        Infinite keys 
LKUZTZZU        75 lives instead of 50
POUZTZZU        25 lives instead of 50 
SXKNKLVG        Don't lose life from 'reset' or 'back' options 
SZOEIUVK        Use sword (press 'B') as long as you like 
XXOAZGYA        Now you can move while using sword
IAEEALYP        Must use with the last code for permanent sword-wielding ability! 
GAXEGIZA + GAUEGIZA     Supercharged speed-up
AAXEGIZE + AAUEGIZE     Turbo fuel-injected 16-valve speed-up