TheWoWDBI had the same problem, after trying it a couple times I think I narrowed it down to the quest being bugged so that if the periodic damage from Vortex Vengeance kills him you are not properly credited for the kill.
My final time, I slowly worked him to death with Sky Lightning after weakening him enough with Vortex Vengeance and was properly credited.
Quest
Vortex
A World of Warcraft quest in Ashenvale. Facts and objectives from the current retail game data.
The highest voted Wowhead comments for this page. They are community notes, not TheWoWDB comments.
Pre-quests: Hot Lava and Put Out The Fire.
I had the exact opposite happen. Killed him five times with Sky Lightning with no DOT on him. Then I tried letting the DOT kill him and got credit. If it's bugged for you, might want to try it both ways.
Quest facts
LevelLevel 7-30
ZoneAshenvale
Quest ID13886
Check whether you have already completed this quest
in-game: /run print(C_QuestLog.IsQuestFlaggedCompleted(13886))
Requirements
FactionAlliance only
Read from the Blizzard quest API.
What to do
StorylineAshenvale, Alliance, step 35 of 50
RewardsBlossom of the Earthen Ring, 
Subduer's Gloves, 
Belt of Equilibrium, 21g, 5,150 XP
Blossom of the Earthen Ring, Subduer's Gloves, Belt of Equilibrium, 21g, 5,150 XPDescription
The time has come, {name}. When you have steeled yourself we will speak again and I will summon forth a whirling vortex to speed your way up to the skies over Thunder Peak. Channel the power of the Earthen Ring through the elemental to slay Lord Magmathar so that we may bring him into balance once more.
Where to go
Pins are the quest’s own POI points from the current retail client, projected onto the in-game zone map. The game marks one blob as the quest’s turn-in; the rest are objective areas. Points that fall outside a map’s window are dropped rather than guessed at.
Turn-inObjective areaObjective areaIn-game waypoint: /way #63 52.1 56.5
Coordinates
- Turn-inAshenvale 52.1, 56.5
/way #63 52.1 56.5 - Objective areaAshenvale 48.1, 39.2
/way #63 48.1 39.2 - Objective areaAshenvale 52.3, 56.8
/way #63 52.3 56.8
Map coordinates of the pins above. An area the client draws as a shape is given by the centre of its points.
Nearby on the Ashenvale map
- Put Out The Fire same spot
- Hot Lava about 10 yards
- Desecrate this Fire! about 390 yards
- A Disturbance in Ashenvale about 960 yards
- The Light of Elune about 970 yards
- Knives of the Forsaken about 970 yards
- Ze Gnomecorder about 1,120 yards
- Field Test: Gnomecorder about 1,120 yards
- Burn, Baby, Burn! about 1,120 yards
- Return to Stardust about 1,140 yards
Quests whose map markers the client places closest to this one on Ashenvale, nearest first. Distances are straight lines between the markers.
Getting there
Alliance flight points closest to the quest’s turn-in marker on Ashenvale:
- Astranaar, Ashenvale
- Stardust Spire, Ashenvale
- Emerald Sanctuary, Felwood
From the turn-in, the objective areas lie:
- Objective area
Straight-line distances in yards between the quest’s own map markers (QuestPOI) and the client’s flight-point positions (TaxiNodes); flight paths and terrain are not modelled.
Community notes from Wowhead · 42 comments
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Choose one of these rewards:
Money21 gold
Experience5,150 XP
Other quests on the Ashenvale map
Reward details
Pick one of these
TypeArmor Held In Off-hand
Item level15
BindingBinds when picked up
Stats+4 Stamina, +5 Critical Strike, +7 Intellect
Suited toDiscipline, Holy, Shadow, Affliction, Demonology, Destruction, Devastation, Preservation, Augmentation, Mistweaver, Balance, Restoration, Arcane, Fire, Frost
Sells to vendors for24 silver82 copper
TypeLeather Hands
Item level15
BindingBinds when picked up
Armor5
Stats+3 Agility or Intellect, +5 Stamina
Suited toBalance, Restoration, Mistweaver, Devourer, Vengeance, Feral, Guardian, Brewmaster, Subtlety, Outlaw, Assassination, Havoc, Windwalker
Sells to vendors for14 silver61 copper
TypePlate Waist
Item level15
BindingBinds when picked up
Armor10
Stats+3 Strength or Intellect, +5 Stamina, +4 Haste, +6 Critical Strike
Suited toHoly, Unholy, Protection, Retribution, Arms, Fury, Blood, Frost
Sells to vendors for14 silver67 copper
TypeMail Hands
Item level15
BindingBinds when picked up
Armor7
Stats+3 Agility or Intellect, +5 Stamina
Suited toElemental, Restoration, Devastation, Preservation, Augmentation, Marksmanship, Beast Mastery, Survival, Enhancement
Sells to vendors for14 silver39 copper
Item facts are the current retail client’s (ItemSparse); the specialisations for a pick-one item are the ones the Blizzard quest API lists; faction and currency text is the client’s own. Lowest listed price = the US commodity auction house now.
Storyline
Ashenvale, Alliance
Part 35 of 50.
Previous: Go With The Flow · Next: A Shameful Waste
- 30True Power of the Rod
- 31Corrupting Influence?
- 32Worgen Wisdom
- 33A Not-So-Charmed Life
- 34Go With The Flow
- 35Vortex
- 36A Shameful Waste
- 37The Lost Chalice
- 38Vile Satyr! Dryads in Danger!
- 39The Branch of Cenarius
- 40Satyr Slaying!
- 41Stopping the Rituals
Showing steps 30 to 41 of 50.
Storyline order is the client’s own QuestLine data from the current retail build.
Where this quest fits
Before this quest
Taken from the storyline's own step order.
- Go With The Flow
<The worgen stares at you intently before launching into his request.> The volcano threatens to engulf all of Ashenvale if we do not act quickly. Let me assure you, this was no natural eruption. My sister, Sabina, is powerful.
After this quest
Taken from the storyline's own step order.
- A Shameful Waste
Welcome to Forest Song, <class>. Where you see tents, there will one day be buildings, but such ambition requires a steady stream of materials.
Other quests with this name
This one: Alliance only · Ashenvale · Level 7-30.
Also counted by Ashenvale Quests
Its criteria name 12 quests; others include:
- Respect for the Fallen
- Stopping the Rituals
- The Forest Heart
- Return Fire
- Recover the Remains
- The Goblin Braintrust
- The Last Stand
- The Lost Chalice
The storyline at a glance
Ashenvale, Alliance has 50 steps, from Bathran's Hair to The Forest Heart.
Maps its steps are placed on (steps per map): Ashenvale (50).
Other storylines on the Ashenvale map
- Ashenvale, Horde
- The Warchief's Command
- Stonetalon Mountains, Alliance
- In Darkest Night
- Ashenvale, Everyone
- Battle Pet Tamers
Steps, storylines and map placement from the client’s QuestLine, prerequisite and QuestPOI data; neighbouring quest text is Blizzard’s own (quest API), shortened to its opening sentences.
Achievements
Completing this quest counts toward this achievement.
- Ashenvale Quests: its criteria name 12 quests, this one included.