I mostly agree with what was said. First, yes it actually is a good shield. If you never use it, maybe you only play earth rush. In any type of slower deck it is really good. If you talk about the cost? Well the near neighbours are the Jade shield/permafrost. Cost is the same, but they have very good abilities. (Jade has 2!) The earth ''ability'' is an extra damage block of 1. Against high hitters that is negligable but against swarmers it is really good. Of course permafrost is good against anything. It has the potential to block 2 and block half the damage on top.
Seeing what this does, I get the feeling the cost cannot be justified. There are other shields for 3/4 quanta that block half the damage. -1
is not unreasonable, certainly for the upgrade. If you have to pay 2 extra
for 1 block, it is barely an upgrade anyway, more a different version.