Found a weird bug with X marks the spot. I spammed it on one of the creeps and after the 3rd X (out of about 5) the unit disappeared, but a few seconds later it came out of the last X's spot visible again.
Ghan has said he has fixed this. Monovertex please confirm this fix. This was only a problem with people that had signatures in the upper levels like not the special members but the respected members.