Build up top of cake with fondant to increase height. Divide fondant and tint 10 oz. yellow, 1 oz. each pink, orange, and violet, 4 oz. green. Prepare cake for fondant covering by icing in buttercream icing and cover with rolled fondant.
Roll out fondant 1/8 in. thick and cut circles using large open end of tip 2A. Attach to cake using damp brush. Roll out green fondant 1/8 in. thick. Cut 1 x 4 in. strip and fringe long edge with 3/4 in. long slits 1/8 in. apart.
Roll up and attach to hat peak with damp brush. Cut 1 x 2 in. strip of green fondant; fringe both long edges 1/8 in. apart 3/8 in. deep. Fold in half, attach to bottom edge of cake with icing.