Units and Shields

[Kilted Raven]

Maybe we should consider a general Q&A thread so that the GR folk can respond in one place if they'd like to clarify stuff.

Got one on unit creation. The Defence basic order (page 180) says to add the unit's shield rating on to the roll if the unit has a shield. Also we have a Shield Wall advanced formation to use.

However there's nothing in the unit descriptions or stats to indicate which units have shields, and if so, what kind of shield they're meant to have. I can't work it out from the stats either. Personal Guard have upgraded armour of 10/-6/2, which implies Full Plate, but also implies no shield.

Are shields meant to be purchasable for units in some way?
If not, is there something to indicate which units have shields and what size?
And if so, is there something for units that don't have a shield (like Greatsword units)?