Weight Traits Tweaks (#149)

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# Description

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Makes the Heavyweight and Lightweight Trait mutually exclusive from each
other.

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# Changelog

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:cl:
- tweak: Tweaked Weight Traits to be mutually exclusive.

Resources/Prototypes/Floof/Traits/physical.yml

@@ -95,6 +95,10 @@
     species:
     - Felinid # They don't need to be lighter
     - Rodentia
+  - !type:CharacterTraitRequirement
+    inverted: true
+    traits:
+    - Heavyweight
   functions:
     - !type:TraitAddComponent
       components:

Resources/Prototypes/_DEN/Traits/physical.yml

@@ -12,6 +12,10 @@
     inverted: true
     species:
     - Oni
+  - !type:CharacterTraitRequirement
+    inverted: true
+    traits:
+    - Lightweight
   functions:
     - !type:TraitAddComponent
       components: