Someone asked me if I would make a list of the best spells in AQ so this is what I think:
MegaInferno (Fire):

Location: Guardian Tower Shop
Level: 77
Price: 70,000
Sellback: 23,335
Hits: 6
Element: Fire
Attack Type: Magic
Damage: 8-36; 8-36; 13-48; 8-36; 8-36; 13-48
Stats: 140%; 140%; 170%; 140%; 140%; 170%
BTH: +20% per hit
Mana Cost: 293
Description: A 6-Hit attack that is sure to leave nothing but a pile of ash where you enemy was standing!
Frost Elf Attack (Fire):

Location: Z-Token Shop
Level: 89
Price: 11,065 Z-Tokens
Sellback: 9,958 Z-Tokens for the first 48 hours, then 5,532 Z-Tokens
Hits: 10
Element: Fire
Attack Type: Magic
Damage: 8-13, 8-13, 8-13, 8-13, 8-13, 8-13, 8-13, 8-13, 8-13, 34-50
BTH: +10%, +10%, +10%, +10%, +10%, +10%, +10%, +10%, +10% +20%
Stats: 100% Stats per hit
Mana Cost: 180
DESCRIPTION
Frost Elves are a little-understood breed of Elves that are short of stature, and enjoy collecting Frostval gifts. These Frost Elves are armed with weapons and pets from Frostvals past, and ready to inflict heavy fire damage on your icy foes!
Riptide (Water):

Level: 80
Price: 80,000
Sellback: 26,665
Location: Talk Like a Pirate Day Shop
Element: Water
Cost: 267 MP
Hits: 6
Element: Water
Attack Type: Magic
Damage: 11-33 plus 135% Stats each
BTH: +25 plus Stats each
DESCRIPTION
The souls of pirates lost at sea help you churn up deadly waters to send your foes to Davy Jones' Locker!
Brilhado Feathers (Wind):

Level: 80
Price: 85,000
Sellback: 26,665
Location: Orb Of Creation: Deep Lake
Element: Wind
MP Cost: 297
Hits: 8
Type: Magic
Element: Wind
Damage: 9-27 plus 105% Stats each
BTH: +24 plus Stats each
DESCRIPTION
Magically-charged Brilhado wing feathers strike your opponent!
Ice Nine (Ice):

Level: 90
Cost: 95,004 Gold
Sellback: 31,668 Gold
Location: Warlic's Advanced
Mana Cost: 351
Hits: 9
Element: Ice
Attack Type: Magic
Damage: 9-27
Stats: 108% per hit
BtH: +27%
DESCRIPTION
The spell is so cold that some believe it is the ultimate ice spell. It does 9 hits of 9-27 damage each with +27 BtH, each hit.
Earth Fury (Earth):

Location: Guardian Tower Shop
Level: 77
Price: 70,000
Sellback: 23,335
Hits: 6
Element: Earth
Attack Type: Magic
Damage: 14-30; 14-30; 19-42; 14-30; 14-30; 19-42
Stats: 140%; 140%; 170%; 140%; 140%; 170%
BTH: +20% per hit
Mana Cost: 293
DESCRIPTION
One of Warlic's personal spells, Earth Fury pulls forth a series of deadly rock spikes from the ground to impale your enemies! 70-230 earth damage.
MegaShock (Energy):

Location: Guardian Tower Shop
Level: 77
Price: 70,000
Sellback: 23,335
Hits: 6
Element: Energy
Attack Type: Magic
Damage: 11-33; 11-33; 16-45; 11-33; 11-33; 16-45
Stats: 150%; 150%; 185%; 150%; 150%; 185%
BTH: +17% per hit
Mana Cost: 293
Description: Warlic's favorite energy spell unleashes and electric blast of power that will shake your enemies to their very core!
Supernova (Light):

Location: Z-Token Shop
Level: 89
Price: 11,065 Z-Tokens
Sellback: 9,958 Z-Tokens for the first 48 hours, then 5,532 Z-Tokens
Hits: 10
Element: Light
Attack Type: Magic
Damage: 8-13, 8-13, 8-13, 8-13, 8-13, 8-13, 8-13, 8-13, 8-13, 34-50
BTH: +10%, +10%, +10%, +10%, +10%, +10%, +10%, +10%, +10% +20%
Stats: 100% Stats per hit
Mana Cost: 180
DESCRIPTION
Assail your enemies with 10 hits of pure elemental light! Give the bad guys a sun tan they'll NEVER forget.
Illuminate Ultra (Light):

Location: Warlic's Advanced Spells
Level: 80
Price: 80,000
Sellback: 26,665
Hits: 6
Element: Light
Attack Type: Magic
Damage: 11-33; 11-33; 16-45; 11-33; 11-33; 16-45
Stats: 130%; 130%; 155%; 130%; 130%; 155%
BTH: +23% per hit
Mana Cost: 297
DESCRIPTION
Many believe this to be the mightiest spell of light magic one can learn before one has learnt enough power to be called an Archmage.
DarkSplatter (Darkness):

Location: Z-Token Shop
Level: 89
Price: 10,955 Z-Tokens
Sellback: 9,895 Z-Tokens for the first 48 hours, then 5,497 Z-Tokens
Hits: 10
Element: Darkness
Attack Type: Magic
Damage: 8-12, 8-12, 8-12, 8-12, 8-12, 8-12, 8-12, 8-12, 8-12, 34-50
Stats: 100% Stats per hit
BTH: +10%, +10%, +10%, +10%, +10%, +10%, +10%, +10%, +10% +20%
Mana Cost: 175
Description: Say the magic words and the dreaded Darksplatter will smash your enemies with 10 hits of Darkness damage!
Ninjat Flip-Out! (Darkness):

Level: 40
Price: 600
Sellback: 300
Location: Jagged Peaks
Element: Darkness
MP Cost: 150
Hits: 4
Element: Darkness
Type: Magic
Damage: 10-24 plus 136% Stats each
BTH: +10 plus Stats each
DESCRIPTION
Summon a magical force that owns the night: Ninjats! 4 ninjats assail your enemy.
Vortex (Wind):

Location: Wizard Games Shop 3
Level: 87
Price: 99,000
Sellback: 49,500
Hits: 3
Element: Wind
Attack Type: Magic
Damage: 28-82 and 321.666667% stat damage per hit
BTH: 21% per hit
Mana Cost: 327
Description: Jackel Sano's favorite spell. Summon the force of a wind vortex, for three powerful hits of wind damage!
Arrows of Virtue (Fire):

Level: 80
Price: 85,000
Sellback: 28,335
Location: The Devourer Saga: The Beginning of The End
Element: Fire
MP Cost: 297
Hits: 2
Element: Fire
Type: Magic
Damage: 38-111 plus 450% Stats each
BTH: +20 plus Stats each
ALIGNMENT EFFECT
This spell deals more damage as you become more Good-Aligned, and less as you become more Evil-Aligned. It deals {100+[Alignment]/1.7}% Base, Random, and Stat damage.
DESCRIPTION
Whoever calls these charged arrows from the sky is in for some real fireworks, and their enemies are in for a surprise!
Vile Shadow (Ice):

Level: 80
Price: 85,000
Sellback: 28,335
Location: The Devourer Sage: The Beginning of The End
Element: Ice
MP Cost: 297
Hits: 2
Element: Ice
Type: Magic
Damage: 38-111 plus 450% Stats each
BTH: +20 plus Stats each
ALIGNMENT EFFECT
This spell deals more damage as you become more Evil-Aligned, and less as you become more Good-Aligned. It deals {100-[Alignment]/1.7}% Base, Random, and Stat damage.
DESCRIPTION
Call forth a chilling shadow to freeze your enemies to their very soul, this spell draws strength from the coldness of your heart.
Nightbane's Apotheosis (Light):

Level: 85
Price: 90,000
Sellback: 30,000
Location: The Devourer Saga: The Manifestation
Element: Light
MP Cost: 318
Hits: 1
Element: Light
Attack Type: Magic
Damage: 83-238 plus 950% Stat Bonus
BTH: +21 plus Stat Bonus
DESCRIPTION
The spirit of Nightbane's human form, Balius, appears on angelic wings to blast a beam of light at your enemy!