Do these orbs require a hit roll? Because quite frankly, I find the image of the party wizard vanishing and leaving behind a bunch of unopposed monsters during the final BBEG battle hilarious. Or even better - a leader, striker or controller suddenly finding themselves plunged into a cage fight with no party and a whole bunch of critters. 
Oh, okay - I know the orbs wont work like this, but it would provide some hilarious "oops" moments.
K.

Oh, okay - I know the orbs wont work like this, but it would provide some hilarious "oops" moments.
K.