Bake cookies. You will need one of each shape for each treat. Prepare dough and roll out to 3/16 in. thick. For turtle shell, cut one circle using second largest (4 1/4 in.) cutter from set. Cut one circle using the largest cutter from set for each treat.
Invert ball pan and spray with vegetable pan spray. Drape smaller circle over every other pan cavity, pressing to smooth surface. Bake 11-15 minutes, or until firm and golden brown. Cool pan on cooling grid 10 minutes. Carefully loosen bottom edges of treat using spatula.
Place larger circles flat on ungreased cookie sheet. Bake 11-15 minutes or until golden brown. Cool on sheet 2 minutes; remove to cooling grid to cool completely.
Cover cookie and marshmallows with melted candy. Melt dark green Candy Melts candy according to package directions. Cut mini marshmallows for legs and tail. Cut marshmallow in half for head.
Position round cookie and marshmallows on cooling grid placed over waxed paper. Pour melted green candy over cookie. Chill until firm.
Fill treats. Fill turtle shell with mini marshmallows.
Make piñata treats. Use melted dark green candy and a cut parchment bag to pipe a line around edge of shell. Immediately attach base. Turn treat right side up. Chill until firm.
Decorate turtle. Use melted dark green candy and a cut parchment bag to attach legs and head to turtle shell, candy eyeballs to head and to pipe smile. Chill until firm.