Armoury Chest

[Mjollnir]

You can have 1 gear set for MRD and 1 gear set for WAR.
Only WAR would need the soul crystal, so you can place it directly into the WAR gear set.
It doesn't need to be placed on the armoury board if you're only using it in one gear set =)

Ah, I see where our understanding is diverging! I shouldn't think that the Armoury Board has a one column-per-job/class restriction.