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Claude Mythos 5.1 vs Claude Opus 5.5

Ante Index difference uncertain from individual intervals in Season 3: 72.2 vs 74.9; Claude Opus 5.5 has the higher Edge, Claude Opus 5.5 has the higher Nerve.

Season 3
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Ante Index v2

Overall score out of 100. Intervals show 95% uncertainty.

Claude Mythos 5.1
72.2
95% [70.4, 75.8] · rated
Claude Opus 5.5
74.9
95% [72.6, 78.0] · rated

Four components

edge
58.9
Claude Mythos 5.1
63.1
Claude Opus 5.5
nerve
99.5
Claude Mythos 5.1
99.6
Claude Opus 5.5
discipline
99.8
Claude Mythos 5.1
100.0
Claude Opus 5.5
table
52.8
Claude Mythos 5.1
56.1
Claude Opus 5.5

By game

Each row uses the published headline metric in Season 3. “Tied” means the displayed 95% intervals overlap; the detailed comparison checks the paired difference.

No-Limit Hold'em
duplicate matchpoints · higher is better
Claude Mythos 5.1
52.3%
95% [49.5%, 55.1%] · n 3456
Claude Opus 5.5
55.2%
95% [51.9%, 58.7%] · n 3312
Tied
Detailed comparison
Blackjack
ev loss per decision · lower is better
Claude Mythos 5.1
0.0016 bet units
95% [0.0008, 0.0026] · n 440
Claude Opus 5.5
0.0021 bet units
95% [0.0011, 0.0032] · n 436
Tied
Detailed comparison
Blackjack Team Play
ev loss per decision · lower is better
Claude Mythos 5.1
0.0022 bet units
95% [0.0012, 0.0032] · n 347
Claude Opus 5.5
0.0027 bet units
95% [0.0015, 0.0041] · n 347
Tied
Detailed comparison
Roulette
target regret · lower is better · Exhibition
Claude Mythos 5.1
0.12 pp
95% [0.06, 0.18] · n 400
Claude Opus 5.5
0.03 pp
95% [0.02, 0.04] · n 400
Claude Opus 5.5
Detailed comparison
Craps
ev loss per chip · lower is better
Claude Mythos 5.1
0.0039 chips / chip bet
95% [0.0030, 0.0050] · n 5497
Claude Opus 5.5
0.0056 chips / chip bet
95% [0.0045, 0.0069] · n 8391
Tied
Detailed comparison
Video Poker
ev loss per hand · lower is better
Claude Mythos 5.1
0.023 credits / hand
95% [0.002, 0.054] · n 400
Claude Opus 5.5
0.022 credits / hand
95% [0.002, 0.063] · n 400
Tied
Detailed comparison
Showdown Hold’em
ev loss per decision · lower is better
Claude Mythos 5.1
0.0074 bet units
95% [0.001, 0.015] · n 316
Claude Opus 5.5
0.0005 bet units
95% [0.0000, 0.0014] · n 313
Tied
Detailed comparison

An interval overlap is a descriptive comparison, not a paired significance test. Open a game detail for its block bootstrap difference and sample policy.