54level cap
Brock fields 5 Pokémon between level 51 and level 54 in Pewter City Gym.
This is around Beat Brock — Pewter City Gym, badge 14 in the story — that page lists everything you can have caught by this point.
Types on this team: Rock ×5Ground ×3Water ×2
| Pokémon | Ability & item | Moves | Base stats | |
|---|---|---|---|---|
 | Graveler Lv 51 RockGround | Ability Sturdy | Defense Curl Rock Slide Rollout Earthquake | HP55Attack95Defense115Sp. Atk45Sp. Def45Speed35Total390 |
 | Rhyhorn Lv 51 GroundRock | Ability Lightning Rod | Sandstorm Scary Face Earthquake Horn Drill | HP80Attack85Defense95Sp. Atk30Sp. Def30Speed25Total345 |
 | Omastar Lv 53 RockWater | Ability Shell Armor | Ancient Power Brine Protect Spike Cannon | HP70Attack60Defense125Sp. Atk115Sp. Def70Speed55Total495 |
 | Onix Lv 54 RockGround | Ability Rock Head Held item Sitrus Berry | Iron Tail Rock Slide Screech Sandstorm | HP35Attack45Defense160Sp. Atk30Sp. Def45Speed70Total385 |
 | Kabutops Lv 52 RockWater | Ability Battle Armor | Rock Slide Aqua Jet Endure Giga Drain | HP60Attack115Defense105Sp. Atk65Sp. Def70Speed80Total495 |
How to beat this team
Shared weaknesses. Fighting hits 5 of 5, Grass hits 5 of 5, Ground hits 5 of 5, Ice hits 3 of 5.
Level to be ready for. Lv 54 — Onix, the highest on the team.
Fighting Pokémon you can have caught by this point. From this guide’s own encounter tables, by Beat Brock — Pewter City Gym, badge 14: