Route 118, Route 119 & Weather Institute

1. Crossing Route 118

After beating Norman at Petalburg Gym and receiving HM03 (Surf), head east from Mauville City to the shoreline of Route 118, where you can inspect a rock near the water's ledge for a hidden Hyper Potion. Surf east across the river barrier to meet Steven Stone, who chats about Pokémon training before leaving for Fortree City. On the east beach, speak to the Fisherman and answer "Yes" to receive the Good Rod, search the sand nearby for a hidden Heart Scale, and collect Sitrus Berries and Magost Berries from the soil patch along the eastern path toward Route 123.

Tip: Answer "Yes" to the Fisherman immediately so you do not leave empty-handed.

2. Entering the Route 119 Grasslands

From the Route 118 fork, head north toward Route 119, checking the rocky cliffs along the path to find a hidden Iron. As you enter the southern section of Route 119, rainstorms begin over the very tall grass, which conceals standard route trainers (Lv. 25–28), wild Tropius, and hidden Kecleon. Pick up a Super Repel in the tall grass field, grab Zinc on the west side among the grass, and retrieve a Hyper Potion near the wooden stairs.

Tip: Use the rest room beds inside the small wooden cabin halfway along the route for a free party heal.

3. Exploring River 119

Travel along the parallel river and navigate its waterways and bridges, keeping in mind that Feebas can bite on any fishing rod at a 50% rate on only 6 specific water tiles out of the route's 444 navigable tiles. Pick up an Elixir in the Acro-bike rail shortcut area, and if you ride the Acro Bike, bunny-hop across the thin white rails north of the river to secure a Rare Candy. To find a hidden Leaf Stone, Surf down the riverbank past the waterfalls on the far side of the river.

Tip: Riding the Mach Bike allows you to climb muddy slopes, whereas the Acro Bike lets you hop across white balance rails to claim bonus items like the Rare Candy.

4. Storming the Weather Institute

Approach the suspension bridge to find it blocked by two Team Aqua Grunts, forcing you into the modern research lab facility. Battle through the Team Aqua Grunts Gauntlet across 1F and 2F, tackling Grunts (Lv. 26–28) wielding Carvanha, Poochyena, Zubat, and Mightyena. Reach the second floor to confront Aqua Admin Shelly and her Lv. 28 Carvanha and Lv. 28 Mightyena.

Tip: Carvanha has Rough Skin recoil on physical contact, so strike it with special Electric or Grass attacks, and take out Mightyena with Fighting or Bug moves.

5. Road to Fortree City

With Team Aqua driven away, the suspension bridge opens up; cross north-east to run directly into your Rival (May or Brendan) for a battle. Overcome your Rival's team (Lv. 29–31)—be ready for Lombre's turn-one Fake Out flinch—to earn prize money, a PokéNav Match Call registration, and HM02 (Fly). Afterward, continue along the cleared path straight toward Fortree City.

Tip: Pelipper is 4x weak to Electric moves, and Marshtomp is 4x weak to Grass attacks.

The short version

What matters

• Surf across Route 118 to link western and eastern Hoenn, and grab the Good Rod from the east beach Fisherman.
• Rescue the Weather Institute scientists from Team Aqua to unblock the northern suspension bridge and receive Castform holding Mystic Water.
• Defeat your Rival past the bridge on Route 119 to secure HM02 (Fly) and Match Call registration.

Common mistakes

• Attacking Admin Shelly's Carvanha with direct physical attacks, which triggers Rough Skin recoil damage alongside its high physical attack power.
• Walking away from the Weather Institute 2F scientist without Castform when your party is full; simply access the PC on 1F, clear a slot, and talk to him again.
• Altering the trendy phrase in Dewford Town while actively hunting Feebas, as this scrambles the 6 active fishing spots.

What you can skip

• Searching every single water tile for Feebas unless you are determined to track down its 6 randomly designated tiles.