Invincible Vs. features an original character created for the game in the form of Ella Mental, who was created in collaboration with series creator Robert Kirkman. This provided a unique challenge for the development team, as she was the only character in the game without any source material to pull from outside of a sketch provided by artist Cory Walker. One particular hurdle came in regards to her elemental attacks, due to how demanding the visual effects were compared to other characters.