There are times when a stun is preferable to a Weakness. Speaking as someone who uses shields a lot, I like it. While monsters don't have much to work with, I do know that it is possible to hit hard enough to hurt someone even with a 90 percent weakness on. I use stuns to ensure that I have an extra round to get my shields up.
In this case, this spell is rather situational. It's not the best, but it's certainly not the worst spell out there. It all depends on how you use it.
well the spell uses a lot of pips and stunning is used for extra time healing or another attack. If it stuns them, you will be low on pips and a wasted stun. Then the opponent who has more pips, will cast a big spell on you and tada, you have used up half your health from that spell!
My fire still hasn't gotten to the new world yet (actually about to start azteca). But from reading about the spell, I'd agree with the last line from "Scarlet Nightdream..."s post, its not that bad of a spell, but it would be mostly situational. Like if it were against a boss who heals a lot, or in PvP situations, or as a last second save to stop a boss from killing you and then you finish them on the next turn. So, I'll probably still use efreet most of the time, but King Atorious won't be completely forgotten.
P.S. Do you know if the fire spear from King Atorious will stack with the normal cast fire spear? If so then it might be more useful in some fights.