You have been marked by a powerful creature from the Feywild and its unpredictable magic has changed you, granting you the following benefits and flaws:
- Drop your Constitution by 1 and increase your Charisma score by 2, to a maximum of 20.
- You learn the Misty Step spell and one 1st-level spell of your choice. The 1st-level spell must be from the Divination or Enchantment school of magic. You can cast each of these spells through your mark without expending a spell slot or components. Once you cast either of these spells in this way, you can’t cast that spell in this way again until you finish a long rest. You can also cast these spells using spell slots you have of the appropriate level. The spells’ spellcasting ability is Charisma.
- When you cast a spell through your mark, roll a d4. If you roll an even number, nothing happens. If you roll an odd number, the spell gains an additional effect based on your season described in the Eladrin fey step ability; if the effect requires a saving throw, the DC equals 8 + your proficiency bonus + your Charisma modifier.
- Your mark whispers to you in strange riddles. Whenever you cast a spell through your mark it manifests visibly on your skin and the whispers intensify. They are a constant distraction for 10 minutes afterward.
Option: Greater Fey Powers
At the DM's option, a character who has the Fey Mark feat has a chance of manifesting greater power. Upon reaching 10th level, such a character has a 10 percent chance of gaining an epic boon from among the options in chapter 7 of the Dungeon Master's Guide. If the character fails to gain a boon, they have a 10 percent chance the next time they gain a level.
If the character gains a boon, the DM chooses it or determines it randomly. The character also permanently loses one of their Hit Dice, and their hit point maximum is reduced by an amount equal to a roll of that die plus their Constitution modifier (minimum reduction of 1). This reduction can't be reversed by any means.