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How often do stars like the Sun release superflares of $10^{34}$ erg or more? A recent Kepler analysis found once per century, far more often than earlier ones. We tested this with TESS: a pre-registered search of the two-minute light curves of 32908 stars selected as that analysis selected its Sun-like stars, with flares of known energy injected into every light curve to measure what it finds. It counted 78 superflares where the once-per-century rate predicts 23.4: 3.33 times that rate (interval 2.63 to 4.15), one per 33 years per star, far above the earlier rates. Every planned subset and sensitivity analysis gives a ratio above one. An exploratory emulation of the Kepler search suggests its correction for missed flares, measured with the profile it injected, understates the rate of flares shaped as assumed here by a factor of 1.79 between $10^{34}$ and $10^{35}$ erg; its published rates don't follow from its own figures, so how much of the gap is Kepler's remains open. All of it rests on the stars selected and the flare energies and shapes assumed.

• Published.Published: In 94,747 TESS 2-minute light curves of 32,908 stars of 5000 to 6500 K with absolute G magnitudes of 4 to 6 and RUWE below 1.4 (5,605 star-years), the pre-registered search, with its SAP test corrected after registration to require the uncorrected flux to rise, counted 78 flares of bolometric energy 10^34 erg or more where the rate Vasilyev et al. (2024) measured with Kepler predicts 23.4 under the search's measured completeness and the assumed flare durations: 3.33 times that rate (95% CI 2.63 to 4.15), about once per 33 years per star; the registered code counted 79 (3.37 times, 2.67 to 4.20).
• Published.Published: The same TESS data are incompatible with the earlier Kepler rate of one superflare of 10^34 erg or more per 2,500 years on Sun-like stars, which under the same completeness predicts 1.04 counted flares where 78 were found (Poisson probability below 10^-100).
• Published.Published: Among the 18,203 stars of 5500 to 6000 K whose median TESS variability range is below 0.3%, the 50 counted superflares are 3.63 times (95% CI 2.70 to 4.79) the 13.8 that the rate Vasilyev et al. (2024) give for their Sun-like stars predicts.

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