Well, if it's down to the name, than give your preferences, folks! For me both "guardian" or "void" will do just fine. I'm looking for an upgrade to the shadow bug, manifested in a very experienced, yet still healthy and strong, shadow bug. The role of the bug can be to defend the colony in case of great stress, not only to protect the Shadowbug Queen, but, say, repel any major invasions or try to rescue the nest from natural disasters by, for instance, evacuating Nymphs and wounded Shadow Bugs (veteran bugs will probably be strong enough to lift them). And one can explain their absence in the deepder downs by saying that it's a relatively new colony there and that the bugs generally don't live next to lava, but given how the Shadowlings started on-land war, were forced to migrate northwards, where it's more calm.