Potent Cantrip is a Evocation Wizard feature gained at level 6 in D&D 5e. Starting at 6th level, your damaging cantrips affect even creatures that avoid the brunt of the effect.
Starting at 6th level, your damaging cantrips affect even creatures that avoid the brunt of the effect. When a creature succeeds on a saving throw against your cantrip, the creature takes half the cantrip's damage (if any) but suffers no additional effect from the cantrip.