In Neverwinter Nights, the player character's (PC's) alignment dictates which classes can be selected at level-up. Paladins, for example, must be lawful and good while rogues and bards must be chaotic or neutral. A PC's alignment can shift based on dialogue choices and actions performed by the character. This is the only way to change the PC's alignment without using the console or other hacks or mods. To perform more rapid alignment shifts, use the NWN Alignment Manager mod to rapidly change your character's alignment to suit any given situation.
Download the NWN Alignment Manager mod (see Resources.)
Extract the files to the Neverwinter Nights "Override" folder. This folder is in the main NWN folder, which is usually found at "C:\neverwinterNights\NWN." If the folder does not exist, create one by right-clicking in the NWN folder and then selecting "New Folder" from the menu. Name that new folder "Override."
Load a saved game.
Hit "Enter." In the "Talk" field, type "##DebugMode=1" without the quotation marks.
Hit "Enter." Type "##dm_runscript gnam_1_manually" to bring up the "NWN Alignment Manager" dialogue window.
Hit "Enter." Type "##DebugMode=0" before interacting with the dialogue window that appears.
Select the alignment change that you would like to effect on your character. You can shift your character's alignment along the "Good/evil" axis and the "Lawful/chaotic" axis by one, five or ten. You can select as many changes as you would like, increasing the shift as far as you need it to go. The scale runs from zero to 100 along both axes, with "100/100" being lawful good and "0/0" being chaotic evil.
Select "Exit" from the dialogue window to resume gameplay.
Using console commands can cause errors if not done properly. Always back up any saved games in case a change produces an error.