Cheat Mode
Open the ge3.ini file in the "Gothic3/Ini" folder and change the following line
in Notepad:

[Game]
TestMode=false

to:

[Game]
TestMode=true

You can then press tilde key [~] while playing to bring up the console, and type
any of the following codes:

God - God mode
Invisibility - Invisibility mode
Teach all - Learn all skills (lowers stats to 0)
Kill - Kills selected target
Give [item] - Gives specified item
Give gold x - Gives x gold (doesn't work with patch)
Give money x Gives x gold (doesn't work with patch)
Spawn [item] - Spawns specified item/creature
idkfa - gives you all (items, skills...)
Help - show commands
fullhealth - make you healthy
give Cat_Armor - all armors
give Cat_Weapon - all weapons
give Cat_Artefact - all artefats
control - control character
watch - control camera
teach STR x - set strength
teach DEX x - set dexternity /hunting skill/
teach INT x - set intelligence (ancient knowledge)
teach ALC x - set alchemy skills
teach SMT x - set smith skills
teach THF x - set thief skills
teach HP x - set health
teach MP x - set mana
teach SP x - set energy
teach LP x - set learning points


KEYS:

[F1] - Screenshot
[F2] - Fenster/Vollbild Modus
[F3] - Framerate
[F4] - ?
[F5] - Quicksave
[F6] - Zeitraffer an/aus
[F7] - Slowdown time
[F8] - Reset Character - PRETTY USEFUL!
[F9] - Quickload