The search results also point toward Chinese mobile games. One result for "地下城之王 Lord of Dungeons" describes a "new concept 24-hour management simulation game". While not a direct match, this title establishes a context where players act as "lords" commanding "400+ types of card characters". It is plausible that "Lord Dung Dung" is a fan-made or unofficial nickname for a character in a similar Chinese idle or strategy game, possibly a humorous or derogatory term for a powerful but unpleasant character.
In a digital world crowded with content, "exclusivity" is a major driver of engagement. The "15 Exclusive" implies that this content is not widely available, catering to fans who want something more than the standard offering. sweetmook lord dung dung 15 exclusive
Once I have more context, I'll do my best to help you craft an engaging post! The search results also point toward Chinese mobile games