Related
Type
Black Magic
Level
6
Effect
Paralyzes a foe.
Target
One foe
Element
Status
Status
Paralysis
Price
20,000 gil
Sold In
Crescent Lake
Stun is a seemingly weird Spell, unless you're familiar with the Power Word Spells in D&D. Along with its brethren Blind and Doom, Stun only works on Monsters with less than 300 current HP. On the upside, it always works on those creatures, unless they resist Status magic. It can occasionally be useful, but late in the game most of the Monsters you fight have too much HP to make this Spell immediately useful. Of course, if you aren't a fan of instant KO Spells, Stun is a fine choice of a level 6 Spell.
Type
Black Magic
Level
6
Effect
Instantly kills a foe.
Hit Rate
96%
Target
One foe
Element
Death
Status
KO
Price
20,000 gil
Sold In
Crescent Lake
Reaper is a single-target instant KO Spell that isn't particularly accurate. Further, a lot of Monsters (including all Undead) resist Death Spells. It's a fun Spell to cast, but it's really not very good. Quake is the same level and hits multiple targets, though many creatures resistant to Earth are not resistant to Death. Either way, you're probably better off saving a level 6 Spell slot for some other use.
Break is a significantly better single-target KO Spell than Reaper: it's more accurate, and it's Poison-elemental, making it useful against a different set of enemies. It's even got a good chance of killing Tiamat the first time you fight her! It's not the best Spell, but it beats out some of the other level 7 stinkers.
Sprite
Type
Black Magic
LV
8
Effect
Automatically inflicts KO on one foe with less than 300 HP unless they are resistant to Death-elemental attacks
Target
One foe
Element
Death
Inflict Status
KO
Sold In
Gaia (60,000 G)
XXXX is the third in the line of "Power Word" spells that only work on Monsters with less than 300 HP. Unfortunately, it doesn't work on Monsters resistant to Death, and there aren't a lot of sub-300 HP Monsters you're going to want to use this Spell on. 300 HP isn't a lot to go through by the end of the game anyway. XXXX is anticlimactic at best.