First of all, some enemies are immune to beguile. (certain bosses, i would guess you fought a lost soul, so not really applicable here) Also... I can only imagine what glitches would occur when you beguile an enemy in 1v1 PvE. Lost Souls only know attack spells, but they can't hit themselves, and they can't hit you, because they are on your team. I feel sorry for whatever algorithm that chooses a target. Perhaps the AI decided to resolve this little paradox by just targeting you. I would use Beguile in 2v1 boss fights for maximum effect, beguile the minion the turn before he hits.
So I went to unicorn way to try it out, and when I did use it, The enemy hurt me!?
I thought he was suppose to help me!
(I had nobody else in battle, and the enemy was Death)
So, Did I not use the spell right? Or does it not really do anything?
beguile does not take effect the round it is cast.
so, if you're in first and cast beguile, the enemies have already selected their spells and targets for that round (meaning that they *will* attack you). the following round, the selected enemy will help you (unless he is a boss and/or beguile-immune).
i love using this spell at the high levels. on round one, my necromancer will use beguile on the minion, then watch and laugh as the boss destroys him with some high-pip attack-all spell. it's awesome.