Part 4: Maylene split

Becomes available here: Great Rod, HM02 - Fly

Maylene split opens 8 areas. There are 37 trainers standing in them. The fights at this checkpoint are Barry #3 (Player picked Chimchar), Barry #3 (Player picked Piplup), Barry #3 (Player picked Turtwig), and 1 more.

Where to go

1. Route 209

   Wild: Buizel 60%, Seaking 60%, Croconaw 55%, Corphish 40% +21 more

   Trainers: Pokémon Breeder Albert Lv 38, Jogger Richard Lv 39, Twins Emma & Lil (Double Battle) Lv 42, Poké Kid Danielle Lv 44, Pokémon Breeder Jennifer Lv 39, Jogger Raul (Optional) Lv 89 +2 more

   Pick up: TM19 Giga Drain, DeepSeaTooth, Ether, Great Ball, Great Rod, Heart Scale (hidden), Heart Scale, Heart Scale (hidden) +4 more

2. Solaceon Town

   Wild: Flaaffy 20% · Lv 38, Grumpig 20% · Lv 38, Cacturne 10% · Lv 38, Electrike 10% · Lv 38 +9 more

   Pick up: Every Ball Seal, Green Shard, Heart Scale (hidden), Rare Candy, Shuca Berry (hidden)

3. Route 210 South

   Wild: Mothim 20% · Lv 41, Venomoth 20% · Lv 41, Cacturne 10% · Lv 41, Furret 10% · Lv 41 +9 more

   Trainers: Rancher Marco Lv 41, Jogger Wyatt (Optional) Lv 76, Belle & Pa Ava & Matt (Double Battle) . Lv 45, Pokémon Breeder Johnny Lv 55

   Pick up: TM47 Steel Wing, Dusk Ball, Rare Candy (hidden)

4. Hearthome City → Route 209 Tunnel

   Trainers: ★ Barry #3 (Player picked Chimchar) Lv 40, ★ Barry #3 (Player picked Piplup) Lv 40, ★ Barry #3 (Player picked Turtwig) Lv 40

5. Café

   Trainers: Waitress Kati Lv 90, Gambler John Keating Lv 100

6. Route 215

   Trainers: Ruin Maniac Calvin (Rain) Lv 40, Cyclist Cecelia (Rain) Lv 41, Twins Teri & Tia (Double Battle, Rain) Lv 40, Rancher Gregory (Rain) Lv 42, Black Belt Derek (Rain) Lv 41, Jogger Scott (Optional, Rain) Lv 66 +2 more

7. Veilstone City

   Trainers: Galactic Uranus (Tag Battle with Galactic Cupid) Lv 41, Galactic Cupid (Tag Battle with Galactic Uranus) Lv 40, Trainer Dawn/Lucas (Tag Partner, Player selected Chimchar) Lv 44, Trainer Dawn/Lucas (Tag Partner, Player selected Piplup) Lv 44, Trainer Dawn/Lucas (Tag Partner, Player selected Turtwig) Lv 44

8. Veilstone Gym

   Trainers: Battle Girl Carly Lv 41, Black Belt Daniel Lv 43, Roughneck Rafael Lv 43, Battle Girl Jedrzejczyk Lv 45, Bird Keeper Kahlil Lv 44, Roughneck Magnus Lv 45 +1 more

★ Barry #3 (Player picked Chimchar) — Hearthome City → Route 209 Tunnel

6 Pokémon · level cap Lv 40 (every cap) · Barry #3 (Player picked Chimchar)’s own page

	Pokémon	Moves
	Swellow Lv 38 · Guts · Toxic Orb Nature Lonely	Protect Brave Bird Facade U-turn
	Ambipom Lv 39 · Technician · White Herb Nature Naughty	Fake Out U-turn Double Hit Rage
	Electivire Lv 38 · Adaptability · Expert Belt Nature Mild	Flamethrower Discharge Cross Chop Ice Punch
	Slaking Lv 38 · Truant · Life Orb Nature Adamant	Body Slam Pursuit Rage Sleep Talk
	Dugtrio Lv 39 · Arena Trap · Focus Sash Nature Adamant	Earthquake Aerial Ace Pursuit Rock Slide
	Empoleon Lv 40 · Swift Swim · Sitrus Berry Nature Naughty	Aqua Jet Drill Peck Earthquake Steel Wing

★ Barry #3 (Player picked Piplup) — Hearthome City → Route 209 Tunnel

6 Pokémon · level cap Lv 40 (every cap) · Barry #3 (Player picked Piplup)’s own page

	Pokémon	Moves
	Swellow Lv 38 · Guts · Toxic Orb Nature Adamant	Protect Brave Bird Facade U-turn
	Ambipom Lv 39 · Technician · Silk Scarf Nature Careful	Fake Out Pursuit Double Hit U-turn
	Electivire Lv 38 · Adaptability · Life Orb Nature Impish	Fire Punch ThunderPunch Meditate Ice Punch
	Slaking Lv 38 · Truant · Lum Berry Nature Adamant	Body Slam Pursuit Rage Sleep Talk
	Primeape Lv 39 · Reckless · Expert Belt Nature Hasty	U-turn Close Combat Stone Edge Pursuit
	Torterra Lv 40 · Thick Fat · Leftovers Nature Careful	Earthquake Curse Seed Bomb Stone Edge

★ Barry #3 (Player picked Turtwig) — Hearthome City → Route 209 Tunnel

6 Pokémon · level cap Lv 40 (every cap) · Barry #3 (Player picked Turtwig)’s own page

	Pokémon	Moves
	Swellow Lv 38 · Guts · Toxic Orb Nature Lonely	Protect Brave Bird Facade U-turn
	Ambipom Lv 39 · Technician · Life Orb Nature Brave	Fake Out Pursuit Double Hit U-turn
	Electivire Lv 38 · Adaptability · Lum Berry Nature Naive	Flamethrower Thunderbolt Earthquake Ice Punch
	Slaking Lv 38 · Truant · White Herb Nature Lonely	Body Slam Pursuit Rage Sleep Talk
	Ludicolo Lv 39 · Swift Swim · Leftovers Nature Bold	Leech Seed Scald Ice Beam Giga Drain
	Infernape Lv 40 · Iron Fist · Life Orb Nature Hardy	Mach Punch Close Combat Flamethrower ThunderPunch

Also fought around here

Everything you can have caught by this checkpoint · Open the interactive guide

This game's documentation doesn't say where 31 of its 481 fights happen, so those trainers are on no part of this walkthrough; they are all on the Trainers page. It also doesn't say when 14 of its areas open up, so they are listed together in the last part rather than guessed into the story.