Are you going to hand them the 2 million dollars required to do that?
Viewing post in Allumeria - Voxel Sandbox comments
You don't have to pay to contest it, all you do is dispute the claim, and they have 2 weeks (?) to file suit or it's dismissed. They have probably already filed a dispute.
A DMCA claim is an extra-judicial procedure, it's supposed to occur so everyone doesn't have to go to court (in theory). It's basically a fancy legal notice.