It's a slight buff. Now that Deadnoughts are known for zombie-revivals, why can't we have the Slag Guards in FSC revive some monsters, too? In Vanaduke's location, could it be a problem to add more respawning Zombies, or fiery Bombies around his last phase? Or possibly Vanaduke having a revival ring? Maybe not... but I don't know. It seems out of place for these guys to not have anything to revive with their RezRings.
they do in the new danger mission