The document discusses inspiration from the art styles of four games - Hollow Knight, Limbo, Super Street Fighter II Turbo, and Dragon Ball Fighterz. Hollow Knight uses a unique hand-drawn style and expert lighting. Limbo is entirely in shadow. Street Fighter II has a simplistic UI and sprite-based characters. Dragon Ball Fighterz has clean cel-shaded visuals resembling the source manga. Common features across the research include black-and-white palettes and unintrusive UIs. Most discussed aspects will influence the author's project.