rules updates

add dread wurm and werebeasts
fix backlink for magic items
update rules for + abilities

src/pages/rules/magic.md

@@ -291,6 +291,12 @@ Aged sheets of paper or parchment with magical spells inscribed on them.
 
 Usage: Per normal class restrictions.
 
+### Sources
+
+-   Elvish magic items usually have words in elvish etched or carved on them, often the name of the item.
+-   Dwarvish magic items usually have runes etched or carved on them.
+-   Gnomish magic items usually have their names etched or carved on them in gnomish.
+
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 #### Sentient Weapons