While we're listing horrifying enemies.. how about the rularuu eyeballs? I did the Shadow Shard TF with my Mind Controller and remember them being absolutely awful to deal with. But they also see through invisibility, which may have made it particularly challenging for that character.
I find Mind control particularly useful against Rularuu actually. Even though the eyeballs can't be confused, you've still got a lot of tools to fall back on. Alternating sleeps, holds, and confuse depending on the mob makeup means you can take out at least half of them before a cocky softcapped fellow runs in to get torn to pieces.
Hi all - Im just starting to level a new plant/rad troller and am looking for leveling advice regarding power selection / slotting/ etc. I just dinged 8 and am wondering if I should use Spore or Seeds. I do quite a bit of soloing as I have a lot of time on my hands, but like to team also. Any advice is greatly appreciated. BTW - I have just come back to game after a year + 1/2 or two off. Quite a few changes so anything there is helpful also.
thanks 
Seeds. Definitely seeds. It's speeds up your defeat time and keeps you safe. Also, later on Plant will offer a lot of DoT and pets that will break the sleep. It's quite skippable, especially considering it draws aggro.
Force Field and really anything that grants positional or lethal defense should also possibly be mentioned as an annoyance. It doesn't reduce the Confusion mag but it does make it harder to hit. Mainly a problem when you're up against +3s or +4s. The other Confusion powers (in Mind and Illusion) ignore positional defense so they bypass Force Field completely, and Ice's Arctic Air power is auto-hit (with a random 30% chance to Confuse that is completely unrelated to To Hit rolls, level, or defense).
Global = Hedgefund (or some derivation thereof)