by corbon
It is absolutely allowed, and is not in itself at all unbalancing. The heroes have an answer (Wind Pact) and if the OL does not use Crushing blow regularly enough the Heroes can be very overpowered in their accummulated kit.Its a tool in the OL's kit. Using it comes at a cost - those Lts will be spending all their time moving back and forth from OL's base and hero party and never seiging or doing plot work, just as an immediate example, let alone the opportunity cost of what else those XP or treachery could have been spent on.
Complaints of unbalancing and overpowered-ness almost inevitably come from player groups that ignore the tools or options they have (eg refuse to flee dungeons), get rules wrong (eg see Jackie's Reach + Sweep which explicitly do not combine ever), or just play very badly.