Alignment is one of the central concepts of religion on Discworld. Just as the gods come in various shapes and sizes with different tenets and doctrines to their faiths, the mortal inhabitants of Discworld, including players, have a variety of alignments reflecting, in some way, their habits and attitudes to their surroundings. Each deity requires that a follower's or priest's alignment be in a certain range for rituals and other favours to be granted, so if religion is an important component in your life, you should learn to be careful with actions that affect your alignment.
Given the polarisation of alignment into "good" and "evil", the foremost of these actions will be the killing of another creature. Killing a good creature will generally make you more evil, while killing an evil creature will generally make you more good. It's important to note that the actual act of taking another life is inherently evil, so even if the creature is "neutral", you may become more evil by its death.
There are various ways to detect the alignment of another creature or that of yourself - a crude estimate appears on your score, together with your deity.
The ranges have been deduced from code in the publically released MudLib. The MudLib may not reflect in-game code.
Each of these indicators represents a range of alignment values. The ranges may not be of equal magnitude, for example the number of "very good" NPCs killed to get from "neutral" to "evil" might not be the same as the number to get from "quite evil" to "extremely evil".
The effect of the levers has been deduced from code in the publically released MudLib. The MudLib may not reflect in-game code.
Killing the following NPCs will help you become of "Good" alignment.
Killing the following NPCs will help you become of "Evil" alignment.