- Will the next Mythos-Class model debut as #1? (Text Arena)98¢
This market will resolve to "Yes" if the next Anthropic Mythos-class model added to the Arena.AI Leaderboard (https://arena.ai/leaderboard/text/overall-no-style-control) has the highest arena rank when the table under the "Leaderboard" tab is checked at 12:00 PM ET on the calendar date following the date on which it first appears on the leaderboard. Otherwise, this market will resolve to "No". Any model whose official name includes "Mythos," or "Fable" (e.g., Claude Fable 5.1 or Claude Fable 6), or that Anthropic officially describes as a "Mythos-class" model or similar, will qualify for this market's resolution. Anthropic's other model tiers, such as Opus, Sonnet, or Haiku, will not qualify. Results from the "Rank" column under the "Text Arena | Overall" Leaderboard tab at https://arena.ai/leaderboard/text/overall-no-style-control with style control off (Adjustments: None) and filtered for "Models" will be used to resolve this market. This market will resolve solely based on the specified rank in the Rank column of the leaderboard, regardless of any underlying granular or unrounded data presented elsewhere. A model marked "AutoEval" will not be considered added to the leaderboard. Only ranks displayed without the "AutoEval" label will be considered. If multiple qualifying models are added to the leaderboard on the same calendar date (ET), the highest-ranking model will be used for resolution. Models added to the leaderboard on the calendar date following the initial qualifying model's first appearance will not be considered. If a model is first added to the Arena.AI Leaderboard but is subsequently removed and not re-added, such that it is not displayed on the leaderboard at 12:00 PM ET on the calendar date following its first appearance, its appearance will not qualify as added to the Arena.AI Leaderboard. A qualifying model must be newly added to the Arena.AI Leaderboard. Whether the model was previously released, publicly accessible, in beta, or otherwise available before appearing on the leaderboard is irrelevant for this market. The resolution source for this market is the Chatbot Arena LLM Leaderboard found at https://arena.ai/leaderboard/text/overall-no-style-control. If this resolution source is unavailable at 12:00 PM ET on the calendar date following the date on which the qualifying model first appears on the leaderboard, this market will resolve based on the first subsequent instance at which such a score becomes available on the leaderboard. If it remains unavailable through the end of the seventh day after the qualifying model first appears on the leaderboard or if no qualifying model release occurs by June 30, 2027, 11:59 PM ET, this market will resolve to "No".
Anthropic’s consistent frontier scaling and the verified 1531 Text Arena Elo of Claude Mythos 5 / Fable 5 (released June 2026) underpin the 98% market-implied odds that the next Mythos-class model will debut at #1. Traders view the lab’s release cadence, agentic coding gains, and leaderboard momentum as reliable signals that the successor will clear the top rank on lmarena.ai/text before the December 31, 2026 resolution. No new capability leaks or announcements have emerged since the prior launch, yet historical three-to-five-month cycles and the model family’s benchmark lead sustain consensus. Remaining downside risks center on extended safety or regulatory reviews—particularly around cybersecurity capabilities—compute delays, or an internal choice to skip arena registration entirely.