Duplicated heads, distorted appendages, boundaries exceeded, preliminary sketch, grainy, low-resolution, poorly illustrated hands - Ensure that the artwork does not have any duplicated heads or distorted appendages that might distort the characters' anatomy. Be cautious not to exceed the boundaries of the composition. Avoid preliminary sketch-like quality that can make the poster appear unfinished. Refrain from using grainy textures or low-resolution elements that could compromise the overall quality. Make sure that the hands are well-illustrated and anatomically correct, without any visual anomalies.