Switcharoo

You imbue your attacks with inescapable damage. All to hit attacks will instead become a saving throw. All saving throw attacks will instead become a to hit. If magic missile is casted while under the effects of this spell then its damage is doubled.

If this spell is casted on an unwilling creature then it must make a dexterity saving throw. On a successful save this spell does nothing

attacks using to hit would use your spell casting modifier.

attacks using a saving throw would use your spell save DC. The save type would be the same type you would normally use to add to attack