As it states, this is just an artist role. More than one will be cast of course. This will be generalised, so state when putting in your audition if you have a preference in one of these fields:

Storyboards

Character concepts

Background artist

Lineart 

Colouring

Sketching.

You do not have to confide to just one of these sections! It is just to expand what you may prefer to show and send.