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+Various intended ways modules can alter the system.
+
+## Custom Resources 
+In the `init` hook, you can register custom resources for characters. This is done by defining new key/object pairs on `CONFIG.DH.RESOURCE.character.custom`.
+The data structure is:
+```json
+{
+	id - the resource key
+	initial - the initial numerical value of the resource (stress starts at 6 for instance)
+	max  - the maximum numerical value the resource can reach
+	label - the label shown for the resource, preferably a i18n localizable string
+}
+```
+
+Optionally, you can also define custom full and empty icons for the resource together with the above,
+
+```json
+{
+	images: {
+		full: {
+			value - the FontAwesome icon class or the filepath to the image if 'isIcon' is false 
+			isIcon - if the image is a fontAwesome icon or an image in your filesystem
+			noColorFilter - normally a uniform color is applied to the image via a css filter. If you're using a non-transparent background or just don't want it, then set this to true
+		},
+		empty: {
+			value - see above
+			isIcon - see above
+			noColorFilter - see above
+		}
+	}
+}
+```
+
+Example
+```js
+Hooks.once('init', () => {
+	CONFIG.DH.RESOURCE.character.custom.corruption = {
+		id: 'corruption',
+		initial: 0,
+		max: 4,
+		label: 'Corruption',
+		images: {
+		  full: {
+			 value: 'systems/daggerheart/assets/icons/domains/sage.svg',
+			 isIcon: false
+		  },
+		  empty: {
+			 value: 'systems/daggerheart/assets/icons/domains/sage.svg',
+			 isIcon: false
+		  }
+		}
+	};
+}
+```
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