User blog comment:AYET/The Terracotta Army - Zoro vs Pica/@comment-4374114-20140602145208

I wouldn't be surprised if Pica did create doubles like this but one of the biggest weaknesses of anything created by Pica would be that it must always be in contact with the ground he touches. The army he would create would not be able to move very fast if they can only walk and Zoro could easily disrupt their ability to do anything by cutting out their legs.

The most helpful person for Zoro now would be to have Barty show up. With the barriers he could form one under Pica if at any time he can get him in the air, making Pica's power irrelevant. Though same thing could happen to DonFlamingo, put him in a barrier box to capture him.