Phase 9 section

Pokémon HeartGold & SoulSilver Goldenrod Radio Tower takeover Walkthrough

Rising Badge

Use the Rocket disguise, expose Petrel, and obtain the Basement Key. Exact HGSS encounters, trainers, items, puzzle route, version differences, and completion checks.

By Damodar Sharma Updated July 10, 2026 Walkthrough

Use the Rocket disguise, expose Petrel, and obtain the Basement Key. This combined guide never substitutes original Gold/Silver or Crystal data for the Nintendo DS remakes.

Source maps

Goldenrod Radio Tower 1F, Goldenrod Radio Tower 2F, Goldenrod Radio Tower 3F, Goldenrod Radio Tower 4F, Goldenrod Radio Tower 5F, Goldenrod Radio Tower Observation Deck, Goldenrod Radio Tower Elevator.

Encounter rows0Trainer rows16Visible / hidden / trees1 / 0 / 0

Version scope

HeartGold and SoulSilver are labeled per row. Event-only and external-device content is never presented as normal retail progression.

Route Plan

Enter the Tunnel photo booth for a uniform, climb the Radio Tower, defeat every disguised employee and grunt, beat Petrel's Koffing team, and take the Basement Key.

Wild Pokémon

No random encounter bank is assigned to these source maps. Static, gift, Safari, Contest, or event records appear separately when applicable.

Trainers

Teams are the exact source party records. Moves and held items appear only when the trainer format defines them. Reward = last party member level × 4 × trainer-class multiplier; double battles double the base payout where the engine applies it.

Trainer	Location / order	Full team	Reward	Battle note
Team Rocket GruntSource trainer ID 185	Goldenrod Radio Tower 1F • scripted/system variant	Raticate Lv. 24 Raticate Lv. 24	₽960	Single battle.
Team Rocket GruntSource trainer ID 186	Goldenrod Radio Tower 2F • source tile (3, 14)	Grimer Lv. 23 Grimer Lv. 23 Muk Lv. 25	₽1,000	Single battle.
Team Rocket GruntSource trainer ID 187	Goldenrod Radio Tower 2F • source tile (13, 5)	Rattata Lv. 21 Rattata Lv. 21 Rattata Lv. 23 Rattata Lv. 23 Rattata Lv. 23	₽920	Single battle.
Team Rocket GruntSource trainer ID 188	Goldenrod Radio Tower 2F • source tile (7, 10)	Zubat Lv. 26 Zubat Lv. 26	₽1,040	Single battle.
Team Rocket GruntSource trainer ID 189	Goldenrod Radio Tower 3F • source tile (9, 5)	Koffing Lv. 23 Grimer Lv. 23 Zubat Lv. 23 Rattata Lv. 23	₽920	Single battle.
Team Rocket GruntSource trainer ID 190	Goldenrod Radio Tower 3F • source tile (17, 12)	Weezing Lv. 26	₽1,040	Single battle.
Team Rocket GruntSource trainer ID 191	Goldenrod Radio Tower 3F • source tile (21, 7)	Raticate Lv. 24 Koffing Lv. 26	₽1,040	Single battle.
Team Rocket GruntSource trainer ID 192	Goldenrod Radio Tower 4F • source tile (8, 5)	Zubat Lv. 22 Golbat Lv. 24 Grimer Lv. 22	₽880	Single battle.
Team Rocket F GruntSource trainer ID 198	Goldenrod Radio Tower 2F • source tile (14, 12)	Arbok Lv. 26	₽1,040	Single battle.
Team Rocket F GruntSource trainer ID 200	Goldenrod Radio Tower 4F • scripted/system variant	Ekans Lv. 21 Oddish Lv. 23 Ekans Lv. 21 Gloom Lv. 24	₽960	Single battle.
Scientist GS GarettSource trainer ID 471	Goldenrod Radio Tower 3F • source tile (13, 14)	Magnemite Lv. 27 Magnemite Lv. 27 Magnemite Lv. 27	₽864	Single battle.
Scientist GS TrentonSource trainer ID 472	Goldenrod Radio Tower 4F • source tile (4, 9)	Porygon Lv. 30Moves: Conversion / Conversion 2 / Recover / Charge Beam	₽960	Single battle.
Executive Ariana ArianaSource trainer ID 478	Goldenrod Radio Tower 5F • source tile (11, 4)	Arbok Lv. 32Moves: Wrap / Poison Sting / Crunch / Glare Vileplume Lv. 32Moves: Mega Drain / Sweet Scent / Sleep Powder / Acid Murkrow Lv. 32Moves: Wing Attack / Pursuit / Astonish / Night Shade	₽2,560	Single battle.
Executive Archer ArcherSource trainer ID 485	Goldenrod Radio Tower Observation Deck • scripted/system variant	Houndour Lv. 35Moves: Fire Fang / Roar / Bite / Faint Attack Koffing Lv. 35Moves: Tackle / Sludge / Smoke Screen / Haze Houndoom Lv. 38Moves: Fire Fang / Smog / Bite / Faint Attack	₽3,040	Single battle.
Executive Petrel PetrelSource trainer ID 487	Goldenrod Radio Tower 5F • scripted/system variant	Koffing Lv. 30Moves: Tackle / Selfdestruct / Sludge / Smoke Screen Koffing Lv. 30Moves: Tackle / Selfdestruct / Sludge / Smoke Screen Koffing Lv. 30Moves: Tackle / Selfdestruct / Sludge / Smoke Screen Weezing Lv. 32Moves: Tackle / Explosion / Sludge / Smoke Screen Koffing Lv. 30Moves: Tackle / Selfdestruct / Sludge / Smoke Screen Koffing Lv. 30Moves: Tackle / Smog / Sludge / Smoke Screen	₽1,200	Single battle.
Executive Proton ProtonSource trainer ID 706	Goldenrod Radio Tower 4F • source tile (23, 8)	Golbat Lv. 28Moves: Leech Life / Bite / Confuse Ray / Wing Attack Weezing Lv. 33Moves: Double Hit / Sludge / Smoke Screen / Smog	₽1,320	Single battle.

Items And Hidden Items

Item	Method	Plain-English placement	Source tile
Ultra Ball	Visible item ball	Pick up the item ball in the east part of Goldenrod Radio Tower 4F.	`25, 7`

Puzzles And Systems

Follow the route plan in order; source tiles in the item and trainer tables provide a QA anchor for every placed object.

Completion Checklist

Visit all 7 mapped source subareas assigned here.
Account for 0 random, Headbutt, Safari, Contest, static, gift, trade, or event rows across the per-area tables.
Defeat or deliberately defer all 16 listed trainer records.
Collect 1 visible items, 0 hidden items, and 0 Apricorn trees assigned here.
Finish the stated story, puzzle, schedule, version, and event conditions before moving on.

Sources And Validation

Primary source: pret/pokeheartgold commit 814275e4392cc21eef45a04e6dc8d980010ca2b7.
Layers: encounter banks, map headers, trainer parties, field events and scripts, Headbutt, Safari, Bug Contest, hidden items, Apricorns, phone/Pokégear, and Frontier engine data.
Machine-readable validation report and trainer asset manifest.

Dex quick links

Pokemon in this phase

Koffing