The phrase "most unfaded" implies an item or concept that has retained its original appearance, freshness, or vitality over time, and that stands out from its counterparts. Antonyms for "most unfaded," therefore, would be words or phrases that convey the opposite sense - of something that has decayed, deteriorated, or lost its original luster. Some antonyms for "most unfaded" might include faded, worn, dilapidated, deteriorated, discolored, tarnished, weathered, and old. These words suggest a state of decline or decay, indicating that something has lost its original charm or appeal. The opposite of "most unfaded" thus implies a lack of vibrancy, beauty, or freshness.