During the game, press Tab and type any of the following:

NWCTIM - gives you all magic and 999 spell points
NWCGENERALDIRECTION - lets you see the entire map
NWCALREADYGOTONE - shows all the secret items on the map
NWCTROJANRABBIT - instantly wins the scenario
NWCSIRROBIN - immediate failure
NWCANTIOCH - gives your hero a tent, ballista, and ammo
NWCFLESHWOUND - gives your hero death knights
NWCIGOTBETTER - adds a level to your hero
NWCCOCONUTS - gives unlimited move points
NWCCASTLEANTHRAX - gives maximum luck
NWCMUCHREJOICING - gives maximum morale
NWCAVERTINGOUREYES - extra 35 archangels
NWCSHRUBBERY - +100 all resources and +10,000 gold
NWCONLYAMODEL - build all buildings in your castle
NWCPHISHERPRICE - brighter colors