Gueldre is a tall man wearing a mask and his former uniform.
- Permeation Magic: Gueldre uses this form of magic to make himself invisible and intangible to other types of magic.
- Grimoire: Gueldre possesses a three-leaf clover grimoire, which contains permeation-based spells that he could use in combat.
- Gueldre likes money, social status/position, steak and rare magic items.
- ↑ Black Clover Manga: Chapter 54, pages 6-7
- ↑ Black Clover Manga: Chapter 55, pages 5-6
- ↑ Black Clover Manga: Chapter 55, page 6
- ↑ Black Clover Manga: Chapter 55, page 5
- ↑ Volume 7