Daughter of the leader of the Undead Legion's acolytes and scholar in xanthous and sorcery, Yellowfinger Heysel is a devoted follower of Rosaria, Mother of Rebirth and a member of her loyal Fingers, along with Ringfinger Leonhard, Creighton of Mirrah and Longfinger Kirk. She comes clad in the Xanthous Set and wears the Obscuring Ring, rendering her invisible at a distance.
She comes armed with the Heysel Pick, a weapon named after her, which allows her to quickly combine casting sorceries while in the middle of an encounter. Throughout the battle, she will occasionally switch to a Light Crossbow instead.
Her main method of attack consists in constantly casting Farron Hail, unleashing a quick barrage of small Magic-based projectiles at great speed. She sometimes combines this attack with a casting of Great Farron Dart, attempting to make her enemies fall off-balance and inflict heavy damage. She may rarely attempt to sneak up on the player using Chameleon.
- If the player is embered, she invades as a dark spirit in the marshlands area, near the Crucifixion Woods.
- Invades as a dark spirit in the poisonous swamp, near the brazier found to the right of the main gate.
- Can be summoned as a white phantom. Her sign is located next to the tower near the Keep Ruins and will only appear after the player has met the following criteria:
The main concern in this battle is that Heysel invades unexpectedly in heavily populated areas, and the Obscuring Ring she wears gives her the advantage of surprise at the beginning of the fight. This may prove to be dangerous the first time she invades in the Road of Sacrifices, as the player may be already with their hands full, perhaps fending off a group of Lycanthrope Hunters, or worse yet, a Great Crab.
However, perhaps her most dangerous appearance takes place in the Farron Keep, where enemies are stronger and the player may be already poisoned and with their mobility compromised due to being wandering through deep water. If this happens, it is of utmost importance trying to get away from the rest of the enemies and look for solid ground as soon as possible.
Furthermore, one of the biggest problems when Heysel invades in this location is actually finding her, as she will be invisible at the beginning and it can become difficult to locate her throughout all the great swamp. A simple method to find her is to head to the third brazier (or the first one, if exploring counter-clockwise) and, most surely, she will appear near the cave guarded by several Basilisks, where the Golden Scroll and the Antiquated Set are found. Additionally, she will reveal her presence every now and then by casting spells at a distance.
Heysel usually attacks by constantly casting Farron Hail, where she unleashes a quick barrage of Magic-based projectiles. She will be unable to move or even turn while the duration of the spell, though, leaving her stuck and facing in one direction for a couple of seconds. The player may take this opportunity to flank her and score some hits.
Occasionally, she will hold her weapon with both hands and rush forward; when this happens, the player may receive her with an attack of their own. She staggers easily and many subsequent hits may be dealt to her until stamina runs out. If she takes out her crossbow, just move to the sides and try to approach her to score more hits.
She will try to lure the player into fighting on her territory (e.g.: the poisonous swamp), but the player may do the same and force her to chase them to higher ground.
- Heysel wears the Obscuring Ring, limiting the player's ability to see her from a distance.
- Heysel can heal up via Estus Flask up to two times per encounter.
- Upon her defeat, the player will be awarded two, three or even four Estus Flask refills.
- If the player has defeated Heysel at least once and then offers a Pale Tongue to Rosaria in the Cathedral of the Deep, she will become summonable in the Farron Keep and teach the "Proper bow" gesture.
- Whether or not Heysel has been defeated both times, a non-hostile Man-grub will eventually appear at Rosaria's Bed Chamber. Upon killing it, it will drop a Heysel Pick and the Xanthous Crown.