Small heads-up first: i myself do not use cheat codes unless it can aid me in what otherwise could be an unresolvable situation. Cheating can ruin your continuity in this kind of RPG's, in my opinion. More than once though, i used cheat codes in a hopeless battle, learning how things resolve, to afterwards succeeding in the same battle without (ab)using the codes. Anyways, here's the explanation, enjoy! ;)

While playing the game, press [Shift] + D to display the "What do you want?" prompt. Then, type one of the following codes and press [Enter] to activate the corresponding cheat function. Note: Enabling cheat codes will prevent medals from being earned until you leave the current region.

Result: Cheat Code
+500 gold: iampoor
Full HP: healmenow
Full Vitality and reset all ability cooldowns: rechargeme
Get War, Resistance, Shield Chant, Haste: shieldsup
Party gains a level: iamweak
Display all NPCs on map: showmeall
Disable "showmeall" code: dontshowmeall
Main character gets a cake: giveasnack
Restore Jenell's loyalty: sorryjenell
Restore Nathalie's loyalty: sorrynathalie
Restore Sevilin's loyalty: sorrysevilin
Restore Shima's loyalty: sorryshima
Reset character's skill points and abilities: retrain
Teleport back to Avadon: backtoavadon
Display current zone and x/y coordinates: whereami
Display frame rate: fps

https://www.cheatcc.com/pc/avadontheblackfortresscheatscodes.html
Russian translation by gignorie