Chthonians

Chthonians are worm-like creatures who live near the Earth's core. They appear in Poptropica Worlds during the Crisis Caverns island quest as the enemies of the Mole People. The war between these species causes volcanic disruption in the Caldera State Park.

Development
Early plans of Crisis Caverns in 2013 reveal Chthonians in a similar role as their final role.

The rough sketch provides a range of emotions and poses for the chthonian - curious, provoked, irritated, angered, or lulled to sleep. The second and third screenshot were both taken in Adobe Illustrator, and close inspection of these reveals the other files open in the program. This includes "monster_worm5.ai", "MonsterWorm_Rig.ai", "old_lady_parts_CC.ai", "Char_Rig_CrazyComet_whiteskin.ai", "Char_Rig_Cook_whiteskin.ai", and "Char_Rig_Cook.ai". This hints that the original name for the chthonians were "monster worms". The other files are pretty straight forward, with "old_lady_parts_CC.ai" probably being one of the two tourists in Crisis Caverns, "Char_Rig_CrazyComet_whiteskin.ai" being Crazy Comet, and "Char_Rig_Cook.ai" being the cook from 24 Carrot Island, Tony.

The fourth screenshot is from the animation software, Spine Professional. It shows the animation rig for the vector illustration from the previous images. The final image is a gif of the final animation that appears in the finished Crisis Caverns during the chase scene.