Enable Console:
Before you can use the cheat codes you must first enable the console. This requires that you edit two files. First, locate the autoexec_a2.cfg file in your INSTALL FOLDER\Profiles folder. Open this file with Notepad and add the following line to the end of the file (in the // Startup section):

setvar dev_console_password = schwinge-des-todes

Next, locate the input_a2.cfg file located in your MY DOCUMENTS\MY GAMES\HOMM5TOE\PROFILES\PLAYERNAME folder. Open this file with Notepad and in the // console section, add the following line:

bind show_console '`'

Activate Cheats:
Once you've done the above, you can bring up the console by pressing ` while playing. Type enable_cheats in the console to activate cheat mode. You can then use any of the following cheat codes by typing them into the console:

add_all_spells
Gives all spells to currently selected hero.

add_gold #
Sets current gold to # and zeroes out other resources.

add_money #
Sets all resources except gold to # and sets gold to #*1000. So add_money 100 gives 100 of all resources and 100000 gold.

clear_money
Sets all your resources to zero.

set_hero_luck_morale X Y
Sets luck (X) and morale (Y) base values for current hero. For example, set_hero_luck_morale 5 3.

add_exp #
Adds # of experience to currently selected hero.

show_player_money #
Outputs resource quantities of specified player into console. Allows you to spy on other players. Example: show_player_money 2.

show_hero_mp
Shows detailed movement point stats for currently selected hero - exact quantity, stats for currently plotted path.

@Win()
Win Mission.

@Loose()
Lose Mission.

@ClearFog ()
Clear fog of war.

@Dragons ()
Give all heroes 1000 black dragons.