Naga's Magic
Here is a list of the spells used by Naga. It's as complete as I know of. I was a little sketchy on the exact definitions (and even the names) on a couple of these spells. So I did a little bit of research at Inverse.org, the virtual Claire Bible of the Slayers Universe. Let's continue, shall we?

Bephis Brig (Spiritual Earth Path): This spell is used to quickly create a tunnel beneath the caster, allowing them to travel downwards in a multi-level dungeon or cave, or make a hasty escape. It's also used by that meanie Lina against her enemies, dropping them in a steep hole! What a bitch!

Bram Gush: The wind elemental version of Flare Arrow or Freeze Arrow. It forms an arrow of wind, which causes a bit less damage than its two counterparts.

Demona Crystal: Upon the casting of this spell, a a mist rises from the ground, and creates a very large shell of ice, completely encasing the target. Possibly the most powerful ice spell?

Detoxify (Dicleary): This spell is used to cleanse the target's body of poisons. Don't ask me WHY, but Naga uses it to break a sleeping spell cast on Lina. Maybe it removes minor magical effects too! :-B

Dil Brand (Explosion Array): The Dil Brand is a mild explosion spell that is difficult to control. However, this doesn't really matter, since neither the explosion that blasts the victim into the air or the fall seem to badly injure the target. This spell is more commonly used by Lina against Naga.

Dimilar Wind: The Dimilar Wind spell fires a high pressure ball of air at the target. It does cause some damage, however, it's mostly used to propel the target/victim a short distance through the air.

Elmekia Lance: Elmekia Lance is a beam of light, crafted from Spirit Shamanist Magic. The spell damages only the target's astral body, making it almost useless against Humans, and deadly to the Mazoku.

Fehlzareid: The Fehlzareid is a magical beam of light that fires in a relatively wide and unpredictable radius. Causes damage to the victim.

Fireball: The Fireball is the fire counterpart of the Freeze Bleed. It's your standard Fireball spell - a ball of flame is fired at the target, which explodes upon contact.

Flow Break: This spell breaks the twisted flow of all black magic enchantments within the area. It does not affect White Magic. I would assume that this is a rather powerful/complicated spell because Lina responds to Naga's casting of it with "I didn't know she knew that spell!"

Freeze Arrow: Naga's most commonly used spell. This spell calls forth Ice into the caster's hand and shapes it into an arrow, which freezes the target. The outcome and the shape of the spell is determined by how much magical energy the caster puts into it.

Freeze Bleed (Freeze Bridd): If the Freeze Arrow is the icy equivalent to the Flare Arrow, then the Freeze Bleed is the icy equivalent to the Fireball. This spell hurls a ball of ice at the target, surrounding it in a large crystal.

Freeze Rain: This is an original spell of Naga. She summons a floating ball of magical energy which shoots arrows of ice in all directions. It's not perfected, and stopping the assault requires you to destroy the magical ball of energy.

Gaav Flare (Garv Flare, Demon Dragon Inferno Howl): Calling upon the power of Gaav, the Demon Dragon King, the caster of this spell fires a fat wad of fire at their opponent. This magical fire has a tendency to keep on going once it has destroyed its primary target, making it a useful spell to use against enemies lined up in a row. Since Gaav was destroyed by Hellmaster Phibrizo, this spell can never be cast again.

Icicle Lance: The Icicle Lance is created by fusing together a few Freeze Arrow spells. It's also the Water Elemental version of the Flare Lance. Just like the Freeze Arrow, it encases the target in ice upon contact, Only with a stronger effect.

Kyu Kyum Spin (Sea Cucumber Spin): A spell that summons a great hoarde of Sea Cucumbers to aid the spellcaster.

Levitation: This spell is self explanitory. It causes the caster to float off of the ground and move around in the air. It can be used to break a nasty fall or to fly for short distances.

Mega Brand (Mega Brunt): A stronger version of the Dil Brand. It doesn't cause much more damage, just affects a wider area.

Mega Vraimer: Another original spell of Naga the Serpent, it is an improvement of the spell Vu Vraimer. The golem summoned is larger, and Spirits are called into the golem, giving it more intelligence, and the ability to respond to more complex commands.

Raywing: A spell that causes air to surround the caster and lift them off of the ground. Mainly for use in flying long distances at great speeds.

Vu Raywa (Stone Ghost): This spell calls forth the power of the earth, giving shape to rocks and stones and breathing life into them. This is actually an original spell of our favorite sorceress, Naga. It's incomplete, which causes the summoned beast to come out looking quite deformed! But, hey! Who has time to research magic when you're too busy getting tanked and playing with slime-halfs?

Vu Vraimer (Spiritual Wall): Well looky here. Chant this spell and you've got yourself a golem the size of Lina's appetite, with the intelligence of gourry to boot! The stone golem rises from the ground, obeying the commands of the caster. Shit, I'd hate to be an enemy of Naga!

Wind Shield: Wind Shield is a spell that forms a barrier of wind around the target. Unlike spells such as the Guumeon, which only protect against magical attacks, this spell protects against all attacks, making it the most popular spell of protection. However, concentration is needed to maintain the shield, which also prevents the caster from performing any other spells simultaneously.

Zelas Gort (Summon Jellyfish): This spell is the counterpart of the Kyu Kyum Spin. Just like Summon Sea Cucumbers, the Summon Jellyfish spell brings forth buttloads of jellyfish to deal with. Unlike Kyu Kyum Spin, however, it can be used to Summon one gigantic jellyfish instead of a bunch of them. What's interesting is in an episode of Slayers: Next, Lina uses this spell against the immortal sorceror Halcyform. After becoming ensnared by the creature summoned, he makes a remark about the spell, and Lina being the smartass that she is, responds with "Yeah, but don't ask me to tell you who taught it to me". This, my fellow worshippers is a reference to Naga. Supposedly, in the Manga, Naga is the only person capable of casting this spell. And since they traveled together, one would assume she taught it to Lina somewhere along the line.

Non-Magic Attacks

"Flat Chested" Attack: In Slayers Great, Naga and Lina go toe to toe, and as Lina jumps through a cloud of dust (caused by one of their spells), she flies at Naga with her fist aimed for her head. Naga, of course will have none of this. She smirks, and says "Flat Chested." Lina's embarrassment causes her to fall flat on her face, putting an end to her attack.

Becker Strike: In Slayers Return, Lina and Naga are traveling with a villager named Becker. They encounter the enemy, Galef, and his henchman in the woods. As Galef's right hand man was about to deliver a death blow to Lina, Naga throws Becker in the air, and drop kicks him, shouting "Becker Strike!" Becker flies towards the enemy in a spiral motion, knocking him and Becker into a tree, and into unconsciousness. HA! And Lina calls Naga a "Pain in the butt", or a "Sidekick". She'd be dead if it weren't for her!