Cut 1 of each dinosaur, reverse standing dinosaur before cutting. Bake and cool. For standing dinosaur, outline with tip 3 and cover with tip 14 stars. Add tip 3 pull-out spikes on spine. Pipe tip 3 eyes, mouth and lines on stomach. For shorter dinosaur, cover with tip 14 stars. Pipe spots, spikes, feet, eye and mouth with tip 3. Set aside.
Bake and cool cake. Ice bottom half of cake green and top half brown. To create lava, use tip 10 to pipe white icing about 4 in. at longest point and ice smooth. Tint piping gel orange and red. Smooth orange piping gel over icing, then add red gel. Position cookies. Pipe tip 8 rocks and add tip 233 pull-out grass on bottom border and around rocks.
To make palm trees, cut spearmint leaves into fourths, dip into granulated sugar. Place 3 leaves in flower forming cup; pipe melted candy into center. Position pretzel stick into candy and let set in refrigerator. Position trees into cake and pipe tip 233 pull-out grass around trees.
Cut cloud pattern from cardstock and print message and designs with marker. Attach lollipop stick to back with melted candy; let set. Insert into cake top with set.