I've posted this in a few spots with no luck but it does seem pretty significant.

I under stand the logic behind not being able to target something you can't see, but if you have spot effect the target should still form. It takes an average of 8-10 seconds to target a spell, but there are inviso abilities out their that pulse within that time breaking TM, virtually making it totally useless.

The Bug is that if inviso does pulse, you don't always lose the spell. Nothing happens, if you were to point out your target and attempt to target them again you get a message saying you already have a target. Never get the fully targeted message, and if you cast, the spell hits a random person in the room which hits with the force of a fully targeted spell. I've had this happen 4 times now.

- Erixx

Yes this is pretty damn annoying, I've had it happen to me a heck of a lot of time, and like he said it can be very dang hard to get casts in between pointing with inviso. Its even a pain as a survival prime with only 2 sec rt on searching, and spotting 1st search every time. But its soooo funny when some random person gets creamed with fat Blood Burst though. Would I be exploiting a bug if I knowingly went and started a fight with a thief outside the empathy guild just to watch blood and acid flying around willy-nilly?