It's still fucking useless. Suicide attacks almost always are. >.>
I think maybe inflicting Life3 before the attack death would make it a little more viable.. and perhaps disabling it under a near death status.
That would make it better... but really, it just seems like a whole lot of useless effort to make one attack useful.
Well, you have to consider what makes it crappy in the first place. Then you also have to double check for imbalance. There are some positive properties that Exploder has over a number of spells, including...
1) Not dependant on spell power
2) Damage ignores enemy defense/magic defense
3) Cheap casting cost
The clear negatives..
1) Death, no duh
2) Too dependant on HP, to the point where other spells surpass in power unless you level up or use HP boosting equipment
3) Enemies benefit more than your own guys.