Hare-mark of the moon

You become an adult as the power within you flourishes, giving you the following benefits:
-You become one size bigger and grow horns.
-You are able to wear items one size lower than yours thank to the magic of your fae lineage.
-You can cast the spell Moon Beam once a day with this feat, no material components required. You can also cast it using any spellslot you already have.
-You gain darkvision of 60ft but you discern in scales of silver.
-You have adventage on your attacks as long as you are directly under the full moon light.