Yilan
Yilan is a Rank A Elite Mark found in Thavnair.
Killing the Elite Mark will reward the player up to 
40 Sacks of Nuts, 
30 Allagan Tomestones of Poetics and 
10 Allagan Tomestones of Aesthetics. Players will also have a chance of obtaining 1 
Cracked Anthocluster, 1 
Cracked Dendrocluster or both.
Coordinates
| Zone | Coordinates | Level range |
|---|---|---|
| Thavnair | (X:14, Y:13) | 90 |
| Thavnair | (X:17.9, Y:11.2) | 90 |
| Thavnair | (X:17.8, Y:15.9) | 90 |
| Thavnair | (X:18.5, Y:11.2) | 90 |
| Thavnair | (X:18.4, Y:23) | 90 |
| Thavnair | (X:20.4, Y:31.2) | 90 |
| Thavnair | (X:25.5, Y:28.3) | 90 |
| Thavnair | (X:27.1, Y:20.7) | 90 |
| Thavnair | (X:28.0, Y:25.8) | 90 |
| Thavnair | (X:29.6, Y:13.6) | 90 |
| Thavnair | (X:32.1, Y:19.9) | 90 |
Spawn Conditions
Trigger
Normal Spawn
Time
4 to 6 hours after killed.
Tips and Tricks
- Soundstorm applies a
Forced March status effect to everyone in range, forcing them to move in the direction shown after 8 seconds. - Mini Light is a large circle AoE that applies
Seduced and 
Minimum debuffs. Make sure you aim the forced march out of it because its next attack kills anyone that is Seduced. 
Devour is followed by Mini Light and kills anyone that is Seduced.- Bog Bomb is an untelegraphed circle AoE on a random target that applies a
Vulnerability Up. - Brackish Rain is an untelegraphed conal AoE on a random target that knocks them back and applies a Vulnerability Up.
Description
“The Au Ra's flavor of Hannish once used the word “yilan” to mean “snake,” though I fear that fails to capture the─frankly repulsive─image of what the Faculty of Medicine has requested you hunt down.
According to reports from the local naturalists, the creature emits aether from its photophores that crushes its prey into a more diminutive form, the better to swallow it whole. Not pleasant, oh no.
Nor is it technically a serpent. Rather, 'tis a quadrupedal scalekin that is equally dangerous on land and in water─though at least it's not subtle.— Lubdahrm, Old Sharlayan Aetheryte Plaza, Old Sharlayan
Lore
“The traditional language of Thavnair's Au Ra once used the word "yilan" to mean "snake," though this particular creature is more of a "scaly quadrupedal monstrosity" as far as the common tongue is concerned. Equally dangerous in water and on land, Yilan emits aether from its photophores to crush its prey into a diminutive form better for swallowing whole—which goes a long way toward explaining why the Faculty of Medicine has asked that it be indisputably dead upon delivery.
— Encyclopædia Eorzea Volume III, p. 299