Coilfang Stalker
Drops from Lady Vashj. It is unknown how Lady Vashj empowers these Fen Striders with their mind-bending powers; even at an early age this creature shows significant psych... Magic type. This pet periodically casts a small pulse that makes nearby critters run in fear.
The Coilfang Stalker is a battle pet taught by the 
Dripping Strider Egg, which drops from Lady Vashj, the final boss of the Burning Crusade raid Serpentshrine Cavern.
Guide awaiting review
Enter Serpentshrine Cavern
Travel to Serpentshrine Cavern and make your way through the raid. You can run both Normal and Heroic 25-man difficulties, and the raid can be soloed at max level.
Defeat Lady Vashj
Find and defeat Lady Vashj at 72.2, 58.9 in Serpentshrine Cavern. She is the final boss of the raid and the only source of the Dripping Strider Egg that teaches the Coilfang Stalker.
Loot the Dripping Strider Egg
After defeating Lady Vashj, loot the Dripping Strider Egg from her remains, then use it to learn the Coilfang Stalker. The raid resets weekly, so you can return each week if she does not drop it.
Complete Raiding with Leashes II
The Coilfang Stalker counts toward the Raiding with Leashes II: Attunement Edition achievement alongside other pets from Serpentshrine Cavern, and completing the achievement rewards the 
Tito's Basket, which teaches Tito.
Tips
The Coilfang Stalker comes in three breeds with nearly identical speed across all three; the biggest stat differences are in Hitpoints (82-point spread) and Power (13-point spread), with Breed 10 being the preferred choice.
In pet battles, this pet excels as a damage dealer using Gravity and Surge of Power, and its Laser ability ignores accuracy reductions, making it a strong option in PVP pet battles.
This pet periodically pulses a psychic wave that causes nearby critters to flee in fear.
See the video guide for additional tips on navigating and completing Serpentshrine Cavern.
