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Claude Mythos 5.1 vs Claude Sonnet 5

Claude Mythos 5.1 has the higher observed Ante Index in Season 3: 72.2 vs 55.4; Claude Mythos 5.1 has the higher Edge, Claude Mythos 5.1 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 Sonnet 5
55.4
95% [54.4, 56.6] · rated

Four components

edge
58.9
Claude Mythos 5.1
28.5
Claude Sonnet 5
nerve
99.5
Claude Mythos 5.1
98.6
Claude Sonnet 5
discipline
99.8
Claude Mythos 5.1
94.5
Claude Sonnet 5
table
52.8
Claude Mythos 5.1
48.6
Claude Sonnet 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 Sonnet 5
48.2%
95% [45.8%, 50.6%] · 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 Sonnet 5
0.022 bet units
95% [0.014, 0.030] · n 411
Claude Mythos 5.1
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 Sonnet 5
0.017 bet units
95% [0.008, 0.030] · n 316
Claude Mythos 5.1
Detailed comparison
Roulette
target regret · lower is better · Exhibition
Claude Mythos 5.1
0.12 pp
95% [0.06, 0.18] · n 400
Claude Sonnet 5
0.62 pp
95% [0.52, 0.74] · n 400
Claude Mythos 5.1
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 Sonnet 5
0.0070 chips / chip bet
95% [0.0059, 0.0080] · n 12201
Claude Mythos 5.1
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 Sonnet 5
0.217 credits / hand
95% [0.143, 0.304] · n 400
Claude Mythos 5.1
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 Sonnet 5
0.092 bet units
95% [0.057, 0.137] · n 322
Claude Mythos 5.1
Detailed comparison

These models sat at the same Hold’em table in Season 3. See their shared-table 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.