From their announcement:
After you have played your first few games of Hail Caesar you’ll know just how many casualties you need to show stamina.
You can of course pick up our metal casualty miniatures but as of now you can get hold of these handy, fun laser-cut casualty markers.
The two sets cover barbarians and Romans and have 40 pieces in each pack. Get hold of yours by heading over to the Warlord webstore.