Heroes of Might & Magic 3  - CheatCodes -  
While in the game, press [TAB] and input the following codes:  

nwconlyamodel = Build all buildings in your castle.  
nwcsirrobin = Immediate failure. 
nwctrojanrabbit = Immediate success. 
nwcavertingoureyes = Hero gains extra 35 archangel. 
nwcantioch = Hero gains tent, ballista and ammo. 
nwcigotbetter = Hero gains 1 level up.  
nwccastleanthrax = Hero gains highest luck. 
nwccoconuts = Hero gains unlimited move points.  
nwcmuchrejoicing = Hero gains top morale. 
nwcalreadygotone = See the full revealed secret item map.  
nwcgeneraldirection = See the full map. 
nwcshrubbery = All sources increased. 
nwctim = Hero gains all magic and 999 spell points.  

- GameTips -  

Tip 1 ----- If it's possible, maintain a money reserve of at least 10,000 to 15,000 gold pieces. This fund can be used to buy armies out of fights they just can't win. This way, you won't lose all your hard-earned units.  
Tip 2 ----- On the larger maps, use one or two token heroes with fast movement rates to move units up from your cities to your powerful heroes out in the field.  
Tip 3 ----- In most scenarios time is of the essence. While you are building up strength, the computer player is busy building up one or two massive armies. Find and destroy them early on, even if it takes two or three armies attacking in quick succession to do it. 
 -Submitted by: lord X