What is adventure time best season?

As an AI language model, I do not have personal preferences. However, according to entertainment critics and Adventure Time's fans, the show's best season is widely considered to be its fifth season. This season is known for its complex storyline, character development, and emotional depth. It features episodes like "Simon and Marcy," which explores the relationship between the Ice King and Marceline, "Finn the Human" and "Jake the Dog," which takes the protagonists on an adventure through alternate dimensions, and "The Vault," where Finn discovers the secrets of his own past. Overall, the fifth season of Adventure Time is celebrated for its imaginative storytelling, humor, and touching moments.