There are four different types of artists, but I'm grouping them all into this one role: thumbnail artists, storyboard artists, background artists, and concept artists. Please let me know which one you are auditioning for. Art should be done digitally with the exception of concept art.
A thumbnail artist would create the thumbnails for the episodes and most other videos regarding the series. You should be able to somewhat copy the art style of the show (Tigz's art style). Basically what the main show would look like but prettier. Thumbnail artist(s) would also be asked to create posters, official art for the show, and if it's a success, art for merch (you would be paid for merch designs). Thumbnail artists are the most important out of all the artists.
Storyboard artists will create a sketchy, shot by shot storyboard of a scene / episode based on the script. I will have notes in the script for what happens in the scene, but you will have a lot of freedom for the shot type and any film elements. I would prefer that you have some filmmaking knowledge of shot types and what effect they can have on the scene.
The role of background artists is pretty self-explanatory, you would create background for the animation. After a storyboard is confirmed, then you will create backgrounds for the animation based on it. I would prefer to have only one background artist to keep the art style consistent, but if there are multiple good choices then the work would be split up (e.g. one person would sketch, one would do lines, one would color, etc.).
Right now as I'm writing this I need concept artists the most. Concept artists will create a character's design based off of their personality and ideas that I have for them. Concept artists will also be asked to create different species that live on Qais, just animal species that live alongside Tuekis like other animals live alongside humans on Earth. They will also create concepts for the environment, buildings, clothing, etc.