Confidence is part of the data: a low-confidence range is an honest answer, a precise-looking number without a basis is not.
Double Rare (ex)high confidence
~1 in 5 packs (~7 per 36-pack box)
Basis: Community large-sample box data: TCGplayer Authentication Center openings, 5,000 packs each for Mega Evolution (Sep 2025) and Phantasmal Flames (Nov 2025) source →
EN print; JP equivalent (RR) runs richer per pack in high-class sets
Ultra Rare (full art)high confidence
~1 in 12 packs (~3 per box)
Basis: TCGplayer 5,000-pack samples (Mega Evolution, Phantasmal Flames); specific UR ~1 in 211 packs source →
Illustration Rarehigh confidence
~1 in 9 packs (~4 per box); a SPECIFIC IR ~1 in 118 packs
Basis: TCGplayer 5,000-pack samples; stable across 2025 sets source →
Special Illustration Raremedium confidence
Set-dependent: ~1 in 101 packs (Mega Evolution) to ~1 in 80 (Phantasmal Flames) — i.e. roughly 1 SIR per 2–3 booster boxes; a SPECIFIC SIR ~1 in 400+ packs. Outlier: Prismatic Evolutions ~1 in 45 packs (~0.8/36 packs)
Basis: TCGplayer samples: 5,000 packs (Mega Evo, Phantasmal), 1,200 packs (Prismatic — smaller sample, wider error bars) source →
Beware: model-based aggregators (e.g. rateTCG) publish very different Prismatic numbers (~1 in 3 packs) that contradict the measured sample — do not use modeled figures
Gold / Hyper Raremedium confidence
Mega era ('Mega Hyper Rare'): ~1 in 1,260 packs ≈ 1 per 35 boxes ≈ 1 per ~6 cases — the scarcest modern EN tier. SV-era golds were far more common, e.g. Prismatic Hyper Rare ~1 in 180 packs (~1 per 5 boxes-worth of packs)
Basis: TCGplayer 5,000-pack samples (Mega era); TCGplayer 1,200-pack sample (Prismatic) source →
Per ETB (9 packs): ≥1 SIRmedium confidence
~20–25% chance (typical 2025–26 set at 1/80–1/101); Prismatic Evolutions ~1 in 4–5 ETBs (~22–25%) at its 1/36–1/45 rate
Basis: Arithmetic derived from TCGplayer measured rates (Rippr and others show the math); not directly measured per-ETB source →
Per ETB (9 packs): ≥1 IRmedium confidence
Roughly 1 IR per ETB on average (9 packs × ~1/9)
Basis: Derived from TCGplayer per-pack rate; aggregator framing