Part 3: Beat Brandon — Dewford Gym, badge 2
Rock Smash opens up in Mauville City.
Beat Brandon — Dewford Gym, badge 2 opens 14 areas. There are 79 trainers standing in them. The fights at this checkpoint are Gym Leader Wattson [Double Battle], Psychic Edward, Breeder Lydia, and 14 more.
Where to go
Slateport City
Wild: Chinchou 70%, Bibarel 60%, Lanturn 60%, Barbaracle 40% +1 more
Trainers: Team Aqua Grunt 1 [Back to Back Battle 1/2], Team Aqua Grunt 2 [Back to Back Battle 2/2], Team Aqua Grunt 2 [Back to Back Battle 2/2]
Pick up: TM03 Water Pulse, TM10 Hidden Power, TM21 Frustration, TM27 Return, TM39 Rock Tomb, TM40 Aerial Ace, TM41 Torment, TM43 Secret Power +24 more
Move tutor: Covet, Flame Wheel, Accelerock, Ice Shard, Silver Wind, Air Cutter, Psybeam, Seismic Toss, Aqua Ring, Leech Seed
Froster Island
Wild: Gyarados 100%, Magikarp 100%, Dragalge 60%
Trainers: ★ Rival Midori, ★ Rival Midori, ★ Store Manager Winona [Double Battle], ★ Store Manager Winona [Double Battle]
Pick up: TM96 Icicle Crash, Leek, Absolite, Beedrillite, Diancite, Galladite, Gardevoirite, Heracronite +8 more
Move tutor: Bubble Smack, Feint Attack, Fell Stinger, Shock Wave, Incinerate, Ancient Power, Moonlight, Mean Look, Aromatherapy, Dragon Rage
Route 110
Wild: Poliwhirl 70%, Lanturn 60%, Poliwrath 60%, Carracosta 40% +7 more
Trainers: ★ Psychic Edward, ★ Psychic Edward, ★ Rival Brendan/May (Grass), ★ Rival Brendan/May (Grass), ★ Rival Brendan/May (Water), ★ Rival Brendan/May (Water) +14 more
Pick up: TM28 Dig, Sharp Beak
Route 118
Wild: Carracosta 100%, Tirtouga 100%, Jellicent 60%, Kecleon 25% +6 more
Trainers: ★ Collector Chester, ★ Collector Chester
Pick up: TM53 Energy Ball, Blazikenite, Sceptilite, Swampertite
Route 117
Wild: Surskit 70%, Masquerain 60%, Pelipper 60%, Omastar 40% +8 more
Trainers: ★ Breeder Lydia, ★ Breeder Lydia, Senior and Junior Anna & Meg, Breeder Isaac, Triathlete Dylan, Bug Maniac Derek +4 more
Pick up: Twisted Spoon, Bright Powder, Light Clay, Shiny Charm
Route 111
Wild: Gyarados 70%, Carracosta 60%, Bibarel 40%, Stunfisk 25% +7 more
Trainers: ★ Winstrate Victor [Back to Back Battle 1/4], ★ Winstrate Victoria [Back to Back Battle 2/4], ★ Winstrate Victoria [Back to Back Battle 2/4], ★ Winstrate Vivi [Back to Back Battle 3/4], ★ Winstrate Vivi [Back to Back Battle 3/4], ★ Winstrate Vicky [Back to Back Battle 4/4] +7 more
Pick up: TM37 Sandstorm, Eviolite, Binding Band, Black Sludge
Mauville City Game Corner
Wild: Bulbasaur, Charmander, Chespin, Chikorita +20 more
Mauville Gym
Trainers: ★ Gym Leader Wattson [Double Battle] Lv 36, ★ Gym Leader Wattson [Double Battle] Lv 36, Bug Catcher Angelo, Guitarist Kirk, Youngster Ben, Guitarist Shawn +1 more
Mauville City
Trainers: ★ Rival Wally, ★ Rival Wally
Route 103 East
Trainers: Aroma Lady Daisy, Twins Amy & Liv [Double Battle], Pokefan Miguel, Guitarist Marcos, Black Belt Rhett, Black Belt Rhett
Trick House Puzzle 1
Trainers: Lass Sally, Lass Robin, Youngster Eddie
Route 118 West
Trainers: Youngster Deandre, Aroma Lady Rose, Fisherman Wade, Guitarist Dalton
Rusturf Tunnel East
Trainers: Hiker Mike
Route 111 South
Trainers: Aroma Lady Celina, Camper Tyron, Picnicker Bianca, Kindler Hayden
★ Gym Leader Wattson [Double Battle] — Mauville Gym
| Pokémon | Ability & item | Moves | Base stats | |
|---|---|---|---|---|
 | Emolga Lv 35 ElectricFlying | Ability Electric Surge Held item Terrain Extender Timid nature · EVs 100Sp.Atk/100Spe | Nuzzle Air Slash Volt Switch Energy Ball | HP55Attack60Defense60Sp. Atk90Sp. Def60Speed103Total428 |
 | Toxtricity Lv 36 ElectricPoison | Ability Surge Surfer Held item Air Balloon Modest nature · EVs 100Sp.Atk/100Spe | Thunderbolt Sludge Bomb Surf Volt Switch | HP75Attack98Defense70Sp. Atk114Sp. Def70Speed75Total502 |
 | Electrode (Hisui) Lv 35 ElectricGrass | Ability Static Held item Expert Belt Modest nature · EVs 200Sp.Atk | Chloroblast Thunderbolt Protect Reflect | HP60Attack50Defense70Sp. Atk80Sp. Def80Speed150Total490 |
 | Rotom (Wash) Lv 36 ElectricWater | Ability Levitate Held item Leftovers Timid nature · EVs 100HP/100Spe | Hydro Pump Discharge Will-o-Wisp Light Screen | HP50Attack65Defense107Sp. Atk105Sp. Def107Speed86Total520 |
 | Probopass Lv 36 RockSteel | Ability Levitate Held item Chesto Berry Bold nature · EVs 100HP/100Def | Dazzling Gleam Power Gem Thunder Wave Rest | HP60Attack55Defense145Sp. Atk75Sp. Def150Speed40Total525 |
 | Luxray Lv 36 Electric | Ability Galvanize Held item Life Orb Jolly nature · EVs 100Atk/100Spe | Return Play Rough Quick Attack Ice Fang | HP80Attack120Defense79Sp. Atk95Sp. Def79Speed89Total542 |
★ Psychic Edward — Route 110
| Pokémon | Ability & item | Moves | Base stats | |
|---|---|---|---|---|
 | Xatu level set by your team PsychicFlying | Ability Magic Bounce Held item Light Clay Bold nature | Light Screen Reflect Tailwind Air Slash | HP65Attack75Defense70Sp. Atk95Sp. Def70Speed95Total470 |
 | Kadabra level set by your team Psychic | Ability Synchronize Timid nature | Psyshock Calm Mind Dazzling Gleam | HP40Attack35Defense30Sp. Atk120Sp. Def70Speed105Total400 |
 | Kirlia level set by your team PsychicFairy | Ability Synchronize Held item Eviolite Modest nature | Psychic Draining Kiss Hypnosis | HP38Attack35Defense35Sp. Atk65Sp. Def55Speed50Total278 |
 | Swoobat level set by your team PsychicFlying | Ability Wonder Skin Modest nature | Air Slash Psyshock Thunder Wave U-Turn | HP67Attack57Defense55Sp. Atk77Sp. Def55Speed114Total425 |
 | Espeon level set by your team Psychic | Ability Magic Bounce Held item Twisted Spoon Timid nature | Psychic Shadow Ball Draining Kiss | HP65Attack65Defense60Sp. Atk130Sp. Def95Speed110Total525 |
★ Breeder Lydia — Route 117
| Pokémon | Ability & item | Moves | Base stats | |
|---|---|---|---|---|
 | Skarmory level set by your team SteelFlying | Ability Sturdy Impish nature · EVs 60HP/60Def | Stealth Rock Pluck Roost | HP65Attack80Defense140Sp. Atk40Sp. Def70Speed70Total465 |
 | Klang level set by your team Steel | Ability Steely Spirit Held item Metal Coat Adamant nature · EVs 60HP/60Atk | Gear Grind Spark Flame Charge Shift Gear | HP60Attack80Defense95Sp. Atk70Sp. Def85Speed50Total440 |
 | Sliggoo (Hisui) level set by your team DragonSteel | Ability Gooey Held item Eviolite Calm nature · EVs 60HP/60Sp.Def | Dragon Breath Water Pulse Flash Cannon Sludge | HP58Attack75Defense83Sp. Atk83Sp. Def113Speed40Total452 |
 | Metang level set by your team SteelPsychic | Ability Clear Body Adamant nature · EVs 60HP/60Atk | Zen Headbutt Metal Claw Bullet Punch | HP60Attack75Defense100Sp. Atk55Sp. Def80Speed50Total420 |
 | Mawile level set by your team SteelFairy | Ability Huge Power Held item Assault Vest Adamant nature · EVs 60Atk/60Spe | Iron Head Covet Sucker Punch Rock Slide | HP65Attack65Defense85Sp. Atk55Sp. Def65Speed50Total385 |
Also fought around here
It also doesn't say when 23 of its areas open up, so they are listed together in the last part rather than guessed into the story.