Located on Route 108, the Abandoned Ship is all that remains from when the S.S. Cactus ran aground. The old vessel has many rusted holes, broken doors, and furniture scattered around. Once slated for demolition, the half-sunken vessel now exists as a refuge for water-dwelling Pokémon. Navigating the structure requires the use of a certain field move in addition to Surf, so some parts will be inaccessible for now.
Three of the four cabins here are connected. Visit the isolated northwest cabin for a Harbor Mail and head downstairs.
Fight Sailor Duncan and collect a Dive Ball from the north-central cabin. Visit the southwest cabin for an Escape Rope and climb the stairs in the northwest corner.
Pass through the north cabin to get a Revive, then go through the south door to reach the outside of the ship. Climb the stairway there to reach the Captain's office.
The Scientist inside is investigating the ship on Captain Stern's behalf. Stern asked him to find a Scanner, but he hasn't had much success. Pick up the nearby Storage Key and return to the basement floor.
Inspect the locked door to the northeast cabin to insert the Storage Key. The key becomes stuck in the lock, but the door opens. Inside, you find TM13 (Ice Beam). After that, head for the south-central cabin. Seawater has flooded into the room, so you can come back and go underwater later in the game.
Trick House - Puzzle 4 (optional)
In Trick House now you can complete the puzzle 4. First, make sure you have a Pokémon that knows Strength.
Mauville City (optional)
When you return to Mauville, you find Wattson standing near the Pokémon Center. He asks for a favor, and explains that the city has an underground sector known as New Mauville. There's a generator inside that hasn't been functioning properly, and he needs you to go and turn it off before the situation gets out of control. He gives you the Basement Key and directs you to the facility's entrance on Route 110. Surf eastward under the north end of Seaside Cycling Road to reach the facility.
Use the Basement Key to unlock the door, and step inside to reach the southeast room.
The lower floor uses a series of colored buttons as a security measure; when stepped on, all similarly-colored doors open while all others close. Step on the blue button in the entrance room and go west. Press the green button in the next room and continue on. Pass by the third button and head north to reach an Escape Rope; collect the item, go to the right to reach an Ultra Ball, back and press the blue button beneath it. Go northwest to find a room with two items, a Parlyz Heal to the left and a Voltorb to the right. Follow the hallway eastward to the north-central room and another pair of items, a Voltorb to the left and a Full Heal to the right; collect the item and step on the green button beneath it. The generator is located in the northeast room; press the red button to shut it down and collect the ThunderStone before leaving the area walking or using an Escape Rope.
With your task complete, return to Wattson outside the Pokémon Center. Inform him that everything is all right in New Mauville, and the grateful Gym Leader rewards you with TM24 (Thunderbolt).
You can now fully explore the route by using Surf. The seaside Route 118 links the west and east sides of the region together. Several new species of Pokémon can be found here, including Manectric, which might be of great value in the upcoming Gym.
The Fisherman on the river's eastern bank believes that Good Rods are really good. Agree with his statement to receive your very own Good Rod, a mid-level fishing rod that can catch even more kinds of Pokémon than the Old Rod.
Gabby and Ty
After your first interview on the south side of Route 111, the intrepid news team can be found searching for their next story on the eastern bank of Route 118's river. Accept their challenge to another Double Battle and be sure to give them a great interview when the dust settles!
Meet up with Steven
As you leave the beach, you are noticed by Steven. He hasn't seen you since your first meeting in Granite Cave, and is pleased to see how much you have grown as a Trainer. He wonders if you will raise Pokémon of all types, or only a certain one.
Route 123 (optional)
Before heading north to Route 119, let's head east to Route 123 for a quick stop. The Berry Master's house, and his extensive backyard garden, can be found on the route's west side.
The Berry Master's wife will give out a Berry each day as well, but the type depends on whether or not you tell her a special phrase. Most answers will result in a common type of Berry, while certain answers will earn a rarer variety. After hearing all five phrases, she will hand out one common Berry from a group of ten every day. At this moment, you can only get the rare Spelon Berry, although you can come back for four others after entering the Hall of Fame.
GREAT BATTLE (only phrase available prior to entering the Hall of Fame)