Vicious Cantrips

Source: Aerune Homebrew
Prerequisite: the ability to cast at least 1 cantrip
You have learned how to turn your magical prowess into a consistently dangerous attack, maximizing every iota of damage you can deal to your enemies.
Choose two of your known cantrips that directly deal damage and require either a saving throw or an attack roll. You may now add your spellcasting modifier to the damage that those two cantrips do. When you level up, you may change which cantrips receive this damage bonus.
This feat does not stack with any other abilities that allow you to add your spellcasting modifier to the damage of a cantrip, such as certain cleric or warlock abilities. Additionally, Eldritch Blast is not an option for this feat.