Horrid Wilting...

[Malin Genie]

Yep, it's like slow, confusion and other multiple-target spells. Advantage that you can be selective amongst friends and enemies - disadvantage that unlike area effect spells you actually have to target them (so you're SOL if they're invisible, misled or otherwise hidden from you and you have no true seeing.)

 

[LokiDR]

The spell affects any number of chosen creatures, as long as no two creatures are more than 60' apart. It's similar to a burst with 30' radius, but more selective. (You can throw horrid wilting into a melee, and target the hostile creatures while leaving your allies unaffected.)

Agreed. This does, however, cause problems if you can't SEE your opponent. So, in some cases I would rather have the 30' burst.