Mordenkainen's Lost Notebook
3-level Transmutation
When you complete this spell, a unicorn’s horn sprouts from your forehead. As an action, you can use the horn to make a melee spell attack. On a hit, the horn deals 1d8 piercing damage plus your spellcasting ability score bonus. The horn is a magic weapon. In addition, you gain the unicorns Charge attack. As a bonus action, you can invoke the power of good to allow the horn to deal an extra 3d6 radiant damage against any evil-aligned creature. You must have a good alignment to use this power. This effect lasts for 1 round, after which the spell’s duration ends. If you are simultaneously under the effect of this spell, unicorn blood, and unicorn heart, the combined magic has an enhanced effect. See those spells for details.