Seafloor Cavern is a subterranean cave deep beneath the waves of Route 128. The cavern is somewhat maze-like, and constantly requires the use of Rock Smash and Strength. In a misty cave, you'll discover TM26 (Earthquake). For more details on getting through the Seafloor Cavern check below.
Underwater Entrance
A cramped underwater area where you'll find the lost submarine that Team Aqua/Magma stole. Without much else to do use dive to surface.
Entrance and Floor 1
Well, you made it, the Seafloor Cavern. Now all that's left is to go inside to Floor 1. Use rock smash on the left rock, then use Strength push the boulder down. You may then push the other boulder to the right. Floor 1 has two Team Aqua/Magma Grunts and three doorways leading to the Entrance, Floor 2 (southeast corner), and Floor 4 (north).
Trainers
| Trainer | |
|---|---|
 |
Team Magma Grunt |
| Trainer | |
|---|---|
|
Team Magma Grunt
|
Floor 2
Accessed from Floor 1's Southeast exit. The south west corner leads to Floor 3's centre exit, and the south east corner leads to Room 3's north west exit.
Before the south west corner, there will be two boulders next to each other horizontally, and two spaces below will be a Smashable rock. In order to reach the south west corner, push the right-hand boulder down two spaces, and walk through the gap between the boulders to reach the Smashable rock.
Before the south east corner, there will be another pair of boulders, sitting diagonally from each other, followed by a Smashable rock to the right of the bottom boulder. Push the top boulder two spaces to the right, and the bottom boulder one space down. Then use Rock Smash to get past the Smashable rock.
Floor 3
When entering from Floor 2's Southeast corner, you will emerge in the centre of Floor 3. Head north to reach the Southwest corner of Floor 4, and head south and hop off the ledge to return to the cave entrance.
When entering from Floor 2's Southwest corner, you will emerge in the Northwest corner of Floor 3. Hop off the ledge to encounter a Team Grunt:
| Trainer | |
|---|---|
|
Team Magma Grunt |
After the battle, hop off the ledge to the right and go North to Floor 4, or South to the Floor's entrance and the cave exit.
Floor 4
The gist of this room is that you can only initially cross it diagonally - meaning that the Northeast corner is inaccessible from the Southeast corner, and vice versa for the west side. However, it is possible for the player to access the Northern corners from each other, negating the need to backtrack through previous rooms to get from one corner to the other.
To get to the Northwest corner from the Southeast corner, push the first boulder North one space. Turn right and push the second boulder North two spaces. Turn left, and push the third boulder West one space. Turn right, and Smash the rock. Head North, and push the fourth boulder North one space. Turn left, and Smash the second rock. Push the final boulder West one space. The Northwest corner leads to the Southern entrance/exit of Floor 5.
To do the opposite (Southeast from Northwest), push the first boulder South one space. Turn left and keep going down the path until the T-Junction. Turn right and push the second boulder one space East. Head South and push the third boulder one space South. Head East and push the final boulder one space East. You can also access the Southwest corner this way by pushing the third boulder further South.
To get to the Northeast corner from the Southwest corner, push the first boulder one space North. Head along the West paths and turn right at the T-Junction. Push the second boulder East and turn left. Head North and push the third boulder North, and then smash the rock to your right. Head East and push the final boulder to the East. The Northeast corner leads to the Southwest entrance/exit of Floor 6.
To do the opposite (Southwest from Northeast), do essentially the same steps but in reverse. Unlike the NW to SE route, you cannot access the other Southern corner this way.
Room 5
Room 6
Room 7
| Trainer | |
|---|---|
| 'Magma Admin Courtney | |
Room 8
First, push the left and right boulders up. The middle boulder is pushed to the side. Push the next middle boulder up, the adjacent boulders to the side. In the last row, push the left and right boulders up, and the middle to the side.
Final Room
TM26 is found at the entrance.
When you reach the southern part of the map, you will see the legendary Pokémon waiting. Then, you will be attacked by the leader of the antagonist team.
| Trainer | |
|---|---|
 |
Magma Leader Maxie |
After the battle, the orb will be used on the legendary to awaken and control it. However, the legendary will simply escape.
If you are playing Pokémon Ruby, the sunlight will become strong over Route 128, through Lilycove City.
Pokémon Found
| Ruby | Encounter Rate | Sapphire | Encounter Rate | Emerald | Encounter Rate |
|---|---|---|---|---|---|
 Zubat
|
90% | Zubat
|
90% | Zubat
|
90% |
 Golbat
|
10% | Golbat
|
10% | Golbat
|
10% |
| Ruby | Encounter Rate | Sapphire | Encounter Rate | Emerald | Encounter Rate |
|---|---|---|---|---|---|
 Tentacool
|
60% | Tentacool
|
60% | Tentacool
|
60% |
| Zubat
|
35% | Zubat
|
35% | Zubat
|
35% |
| Golbat
|
5% | Golbat
|
5% | Golbat
|
5% |
| Ruby | Encounter Rate | Sapphire | Encounter Rate | Emerald | Encounter Rate |
|---|---|---|---|---|---|
| Old Rod | |||||
 Magikarp
|
70% | Magikarp
|
70% | Magikarp
|
70% |
| Tentacool
|
30% | Tentacool
|
30% | Tentacool
|
30% |
| Good Rod | |||||
| Magikarp
|
60% | Magikarp
|
60% | Magikarp
|
60% |
| Tentacool
|
20% | Tentacool
|
20% | Tentacool
|
20% |
 Wailmer
|
20% | Wailmer
|
20% | Wailmer
|
20% |
| Super Rod | |||||
| Wailmer
|
100% | Wailmer
|
100% | Wailmer
|
100% |