| 2026-07-21 | $74.00Outlier | 9 | PSA | PSA 9 Brock's Onix #21 1st Edition Gym Heroes 2000 Pokemon MINT 21/132 | — |
| 2026-07-21 | $26.69 | 8 | PSA | 2000 Pokemon Gym Heroes #21 Brock's Onix 1st Edition PSA 8 NM-MT | — |
| 2026-07-17 | $19.99 | — | Raw | Brock's Onix (21) #21 Near Mint English 1st Edition | — |
| 2026-07-16 | $10.49 | — | Raw | Brock's Onix 21/132 - R Gym Heroes Pokemon 1st Edition MP 21/132 | — |
| 2026-07-13 | $17.49 | — | Raw | 1st Edition Brock's Onix | 21/132 | Gym Heroes | Regular | LP+ | WOTC Pokemon 21/132 | — |
| 2026-07-10 | $13.00 | — | Raw | Brock's Onix (21) #21 Near Mint English 1st Edition | — |
| 2026-07-10 | $24.00 | — | Raw | Pokemon TCG Brock's Onix 21/132 Gym Heroes 1st Edition NM Vintage- Never Played 21/132 | — |
| 2026-07-07 | $19.99 | — | Raw | Pokemon Card - Brock's Onix Gym Heroes 21/132 1st Edition Rare 21/132 | — |
| 2026-07-07 | $19.01 | — | Raw | Brock's Onix 21/132 Gym Heroes 1st Edition Non-Holo Rare Pokemon Card LP+ 21/132 | — |
| 2026-07-03 | $18.46 | — | Raw | Brock's Onix (21) #21 Near Mint English 1st Edition | — |
| 2026-07-01 | $12.99 | — | Raw | Pokemon Brock's Onix 21/132 / 1st edition / LP / Gym Heroes / rare / 21/132 | — |
| 2026-07-01 | $19.99 | — | Raw | Pokemon Card - Brock's Onix Gym Heroes 21/132 1st Edition Rare 21/132 | — |
| 2026-06-30 | $15.99 | — | Raw | Brock's Onix (21) #21 Near Mint English 1st Edition | — |
| 2026-06-28 | $13.83 | — | Raw | Brock's Onix (21) #21 Near Mint English 1st Edition | — |
| 2026-06-28 | $12.25 | — | Raw | Pokemon Brock's Onix 21/132 / 1st edition / Gym Heroes / rare / 21/132 | — |
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