Any ancient magic civilization's ruins that have survived to the present day are likely to contain some things that even today's powerful beings would find extremely troublesome.
They may be deadly traps or strong defense mechanisms. Many ancient ruins possess such powers, akin to tombs, usually anticipating countermeasures against intruders.
Therefore, when ancient ruins are discovered, it is often necessary to carefully arrange exploration plans, or else even if there are many treasures inside, they are of no use if they cannot be brought out.
For this reason, pre-exploration strategy meetings are essential.