Attack magic covers every damage type except Water, though Wind only comes mixed with Flame in the Melton spell. Additionally, Holy and Earth only appear in a single spell each, neither of which is available until fairly late in the game. However, there are always other ways to use these damage types, such as special character abilities or elemental weapons.

Of the three mainstay elements in attack magic, the Ice spells are always (marginally) the strongest in their power class, while two out of three Thunder spells are (just as marginally) the weakest, despite having the highest cost. The Flame spells are always both the least expensive and the most efficient, even Fira, which is weaker than either Blizzara or Thundara. However, Poison is a better early choice for both cost and power, while Holy and (usually) Flare are more economical later on (assuming in all cases that there's no need to hit multiple targets). Of course, if your opponent has a weakness, it usually makes sense to target that regardless. And it goes without saying that Ultima will wreck anything's day, once you manage to learn it.

4 MP. Flame magic damage at 21 power to one or all enemies or allies (one side). 150 hit rate. Power to cost ratio is 5.250.

5 MP. Ice magic damage at 22 power to one or all enemies or allies (one side). 150 hit rate. Power to cost ratio is 4.400.

6 MP. Thunder magic damage at 20 power to one or all enemies or allies (one side). 150 hit rate. Power to cost ratio is 3.333.

3 MP. Poison magic damage at 25 power and 'poison' status to one enemy or ally. 100 hit rate. Power to cost ratio is 8.333, best of any learnable attack magic.

15 MP. Transfers HP from one enemy or ally to the caster at 38 power, but reverses when used on undead targets. Never takes more HP than needed to max out the caster (or, if the target is undead, to max out the target instead). 120 hit rate, unreflectable. Power to cost ratio is 2.533.

20 MP. Flame magic damage at 60 power to one or all enemies or allies (one side). About three times as strong as Fire, and identical except for power and cost. 150 hit rate. Power to cost ratio is 3.000.

21 MP. Ice magic damage at 62 power to one or all enemies or allies (one side). About three times as strong as Blizzard, and identical except for power and cost. 150 hit rate. Power to cost ratio is 2.952.

22 MP. Thunder magic damage at 61 power to one or all enemies or allies (one side). About three times as strong as Thunder, and identical except for power and cost. 150 hit rate. Power to cost ratio is 2.773.

26 MP. Poison magic damage at 53 power and 'poison' status to one or all enemies or allies (one side). 120 hit rate. A bit more than twice as strong as Poison, but much less efficient. Power to cost ratio is 2.038, the worst of any learnable attack magic that doesn't ignore defense.

51 MP. Flame magic damage at 121 power to one or all enemies or allies (one side). About six times as strong as Fire, and identical except for power and cost. 150 hit rate. Power to cost ratio is 2.372.

52 MP. Ice magic damage at 122 power to one or all enemies or allies (one side). About six times as strong as Blizzard, and identical except for power and cost. 150 hit rate. Power to cost ratio is 2.346.

53 MP. Thunder magic damage at 120 power to one or all enemies or allies (one side). About six times as strong as Thunder, and identical except for power and cost. 150 hit rate. Power to cost ratio is 2.264.

25 MP. Sets 'petrified' status on one enemy or ally. 120 hit rate, but always fails on targets immune to instant death, and stamina can also block this.

Break has high accuracy, but like most petrifying attacks, it fails if the target is immune to instant death, not just if immune to 'petrified'. This frequently makes it inferior to Death, which only checks the former, but at least Break can kill undead monsters if they lack immunity.

35 MP. Sets 'incapacitated' status on one enemy or ally, dropping HP to zero. 95 hit rate, but always fails on targets immune to instant death, and stamina can also block this. Fully heals undead targets instead of killing them.

Note that you can use Raise to instantly kill undead enemies. Not only does it eliminate them, it costs less, never misses, and can't be reflected.

[rant]Sorry, but... "pearl"? Changing "Death" to "Doom" is bad enough, but... "pearl"...?? I suppose the spell does look kind of like pearls, but... "pearl"!? If there's really something wrong with "holy"—and I've never understood why there would be—why not "light" or "purify" or even "smite"?[/rant]

40 MP. Holy magic damage at 108 power to one enemy or ally. 150 hit rate. Power to cost ratio is 2.700, efficient for its strength.

Ignoring magic defense is not the same as piercing barriers. That makes it sound unreflectable, which it is not. Why not "Defense-piercing attack"?

45 MP. Defense-ignoring magic damage at 60 power to one enemy or ally. 150 hit rate. Power to cost ratio is 1.333, defense-ignoring.

33 MP. Halves one enemy's current HP (round health remaining afterward up). 120 hit rate, unreflectable, but fails on targets immune to instant death, and stamina can also block this attack.

48 MP. Reduces the HP of each enemy (both sides) to 1/4 of its current amount (round health remaining afterward up). 100 hit rate, unreflectable, but fails on targets immune to instant death, and stamina can also block this attack.

Power to cost ratio doesn't really apply here, but you're getting 50% more damage than Gravity for less than 50% extra cost, and targeting all enemies at once on top of that. While Graviga does have less accuracy against targets with any magic evade, the main concern is stamina blocking, which doesn't care.

According to numerous Japanese sites, デジョン is believed to be short for ディメンション = "dimension".

53 MP. Sets 'incapacitated' status on all enemies (one side), dropping HP to zero. Delays dying counterattacks when it succeeds, which usually means canceling them outright. 85 hit rate and unreflectable, but fails on targets immune to instant death, and stamina can also block this. This spell has less accuracy than the comparable Odin and Raideen kill-all summons, but also costs less and doesn't have a once per battle invocation limit.

62 MP. Unblockable defense-ignoring magic damage at 36 power to all enemies (both sides). Inflicts full damage to multiple targets. Unreflectable and can't be sealed. Power to cost ratio is 0.581, defense-ignoring.

This hits a bit harder than a multi-targeted Flare would if that were a thing, and while it costs more, it also bypasses reflection, evasion, and sealing.

80 MP. Unblockable defense-ignoring damage at 150 power to all enemies (both sides). Unreflectable. Power to cost ratio is 1.875, defense-ignoring.

Ultima is arguably overpowered, with the highest power of any learnable spell and ignoring defense on top of that. The cost is a bit high (though frankly it's low for the output), but the main drawback of the spell is how hard it is to learn. Only the Genjuu Ragnarök and the Hero's Shield teach it, both at a rate of x1, and getting one requires either passing up an extremely powerful sword or spending hours purifying a cursed shield. Tina can learn the spell naturally, but not until level 99, so that's no easier. Ultima also has another, less obvious, weakness: Celes can absorb it with Magicseal Sword.

50 MP. Unblockable defense-ignoring Earth magic damage at 110 power to all enemies and allies (both sides). Always misses targets with 'levitate' status, which includes most enemies that appear to be flying. Unreflectable and can't be sealed. Highest power to cost ratio of any defense-ignoring spell: 2.220, defense-ignoring.

Drawbacks or not, Quake has nearly three quarters of the raw power of Ultima. Try casting it when all allies can absorb, negate, or simply avoid the damage...

75 MP. Reduces the HP of each enemy and ally (both sides) to 1/16 of its current amount (round health remaining afterward up). 100 hit rate, unreflectable, and can't be sealed, but fails on targets immune to instant death, and stamina can also block this attack.

85 MP. Unblockable defense-ignoring Flame / Wind magic damage at 138 power to all enemies and allies (both sides). Unreflectable and can't be sealed. Power to cost ratio is 1.624, defense-ignoring.

The name is believed to be short for "meltdown".

Melton has nearly as much raw power as Ultima does. Try combining it with equipment that absorbs or negates Flame or Wind damage...

3 MP. Displays current and maximum HP and MP, level, and any weaknesses of one enemy or ally. 222 hit rate.

5 MP. Sets 'slow' status on one enemy or ally. 120 hit rate.

The name appears to be a modification of "Aspir", below.

12 MP. Damages one enemy or ally's MP at 12 spell power. 150 hit rate. Power to cost ratio doesn't mean much, but here it is anyway: 0.833.

8 MP. Sets 'silence' status on one enemy or ally. 100 hit rate.

It's more "protess" than "protect", but close enough given that the JP spell names are limited to 4 kana. Possibly short for "protection".

12 MP. Sets 'protect' status on one ally or enemy. Unblockable.

Not sure of the name on this one. Might be short for "sleep" and something else, but... what? Possibly just a random modification for style.

5 MP. Sets 'sleep' status on one enemy or ally. 111 hit rate.

8 MP. Sets 'confusion' status on one enemy or ally. 94 hit rate, low enough to occassionally miss even targets with no magic evade.

10 MP. Sets 'haste' status on one ally or enemy. Unblockable.

10 MP. Sets 'stop' status on one enemy or ally. 100 hit rate.

16 MP. Sets 'berserk' status on one ally or enemy. 150 hit rate.

17 MP. Sets 'levitate' status on one or all allies or enemies (one side). Unblockable and unreflectable. Usable outside of combat.

A kappa is a kind of mythical Japanese water creature, usualy greenish, about the size of a child, and humanoid with a vague resemblance to turtles, monkeys, and otters. They are often held to harass humans, ranging from harmless pranks to widespread destruction.

10 MP. Toggles 'kappa' status on one ally or enemy. 100 hit rate. Usable outside of combat.

The NA description could at least give some idea of what this magic barrier does....

22 MP. Sets 'reflect' status on one ally or enemy. Unblockable.

15 MP. Sets 'shell' status on one ally or enemy. Unblockable.

18 MP. Sets 'transparent' status on one ally or enemy (or removes it, since magic clears the status). Can't be blocked or reflected.

38 MP. Sets 'haste' status on one or all allies or enemies (one side), though why you would choose just one is a mystery. Unblockable.

26 MP. Sets 'slow' status on one or all enemies or allies (one side), but why would you choose just one...? 150 hit rate, more difficult to block than Slow.

As noted on numerous Japanese sites, アスピル (ASUPIRU) appears to be short for "aspirate", to remove something by suction.

Osmosis is a natural process in which liquids pass through semi-permeable membranes from solutions with lower concentrations to solutions with higher concentrations, until the concentrations even out on each side of the membrane. It doesn't apply very well to this spell, even if you consider magic a liquid, since it's a transfer by force and has nothing to do with the concentration of magic. If "aspirate" was too obscure, why not use "absorb" or "siphon"?

1 MP. Transfers MP from one enemy or ally to the caster at 26 power, but reverses when used on undead targets. 150 hit rate, unreflectable. Never takes more enough MP than needed to max out the caster (or, if the target is undead, to max out the target instead). Power to cost ratio is largely meaningless given the special purpose of the spell, but here it is anyway: 26.000.

20 MP. In combat, makes the entire party flee. Always succeeds, even when surrounded, unless at least one surviving opponent has the 'can't flee' flag, which makes it impossible to run from combat. Outside of combat, in most areas with random monster encounters (besides the world map), it teleports the party to the entrance. Usable outside of combat, of course. Can't be blocked, reflected, or sealed.

99 MP. Immediately after casting, the caster gains two bonus turns. Until these two turns conclude, time effectively stops, allowing the user to act at complete leisure without anything else happening. Quick will fail if cast during one of these bonus turns, which makes sense since it would otherwise make for an incredible exploit, especially if combined with the Three Stars accessory. Can't be blocked, reflected, or sealed.

Since time stops during the turns granted by Quick, Cayenne can charge up to any Deathblow Sword skill desired without anything happening in the meantime, though whether this is worthwhile is questionable. For the more magically inclined, combining Quick with the Soul of Thamasa accessory lets a character cast five spells essentially at once by using Quick as the second spell (any spell + Quick on the normal turn, followed by two spells on each bonus turn). Combining with the Three Stars accessory negates the considerable MP expenditure otherwise needed. However, never cast Quick as your first spell when using a Soul of Thamasa. The second spell will count as using up your first extra turn, leaving you with only the second bonus turn to use normally.

I think that takes the prize for the NA version's most confusing description.

25 MP. Removes 'transparent', 'decoy', 'berserk', 'regenerate', 'slow', 'haste', 'stop', 'shell', 'protect', 'reflect', 'reraise', and 'levitate' status from one enemy or ally. Can't be blocked or reflected, which is good since otherwise it wouldn't be of much use for removing 'reflect'. Can be used outside of combat, although the only statuses it affects that last that long are 'transparent' and 'levitate', which you might prefer to keep.

5 MP. Heals one or all allies or enemies (one side) at 10 power. Unblockable, ignores defense, and damages undead targets. Usable outside of combat. Power to cost ratio is 2.00, defense-ignoring, making this the most efficient of the three healing spells.

25 MP. Identical to Cure except for cost and its power of 28. Power to cost ratio is 1.12, defense-ignoring, making this the least efficient.

40 MP. Identical to Cure except for cost and its power of 66. Power to cost ratio is 1.65, defense-ignoring.

30 MP. Removes 'incapacitated' status and recovers 1/8 of target's max HP (ignores defense) for one ally or enemy. Kills undead targets. Unblockable and unreflectable, but misses all undead targets with 'incapacitated' status and all non-undead targets without 'incapacitated' status, displaying as blocked when the target has a shield that enables spell blocking animations. Usable outside of combat.

The Vanish/Doom bug also affects spells that should automatically miss unless the target is incapacitated, so Raise and Araise will work on living targets with 'transparent' status, healing their usual amount.

Silly NA version, Araise doesn't recover any MP, just combat ability and full HP.

60 MP. Removes 'incapacitated' status and recovers all HP. Outside of power and cost, it's otherwise identical to Raise.

3 MP. Removes 'poison' and 'slip' status from one ally. Unblockable and unreflectable. Usable outside of combat.

The prevailing theory on Japanese sites is that Esuna is short for 永久ステータスを治す (eikyuu SUTEETASU wo naosu, cures permanent status). The goes back to FF2, where it could cure only persisting status effects and existed alongside Basuna, which only cured status effects that wore off after combat; the 'ba' likely came from バトル中 (BATORU chuu, during battle). Esuna has since become a more general-purpose status-curing spell, but the name stuck.

15 MP. Removes 'darkness', 'poison', 'petrified', 'silence', 'confusion', 'slip', 'sleep', 'slow', and 'stop' status from one ally. Unblockable and unreflectable. Usable outside of combat.

For comparison purposes, the Panacea item will not remove 'confusion', 'sleep', 'slow', or 'stop', but will remove 'kappa', which Esuna doesn't.

10 MP. Sets 'regenerate' status on one ally. Unblockable.

50 MP. Sets 'reraise' status on one ally. Unblockable and unreflectable.