Template:DamageModifier
The keywords melee, ranged, and finesse can be used to print the corresponding modifier(s) with a link to the Damage Roll page that explains the details:
Usage: {{DamageModifier|melee}}
Result: + Strength modifier
Usage: {{DamageModifier|ranged}}
Result: + Dexterity modifier
Usage: {{DamageModifier|finesse}}
Result: + Strength or Dexterity modifier
The keyword spell can be used to link to spellcasting modifier:
Usage: {{DamageModifier|spell}}
Result: + Spellcasting modifier
Anything that's not one of the specially recognized keywords will just have the word "Modifier" appended and link to ability score modifier:
Usage: {{DamageModifier|Wisdom}}
Result: + Wisdom modifier
If the parameter is completely empty however, then nothing will be printed:
Usage: {{DamageModifier|}}
Result:
(That makes it easier to use in other templates, where a modifier might be optional.)