I actually had a penal legion idea myself. But you can take it if you wish because I've got to many other ideas and I'll never get to it.
A Tyranid/Ork fleet attacks a Penal World, and the guards are insufficient to hold out for long enought until the sector fleet arrives. Either they reluctantly give the prisoners weapons, or the prisoners kill some guards and start fighting back themselves (I never pinned that part down). It's really brutal close quartes fighting in the prison, but most of the inmates are hive gangers anyway, so they are just as suited to the environment as their foes.
__________________ Lord of Fluff and Blood Angels Herald of Nurgle "I wield my power with the Emperor's Authority. Those who would say that I am 'radical' merely have minds too small and impotent to realize all the weapons at their disposal. Do not question my methods on account of these so-called 'Puritans'." -Inquisitor Mathias Rosenadel |