Following Pokemon Omega Ruby and Alpha Sapphire’s seventh gym battle at Mossdeep City Gym, it is time to focus our sights back upon the villainous Team Aqua or Team Magma. Before moving forward, make sure that you have some Pokemon with you that know Strength and Rock Smash, as it is impossible to complete this section without them. Also, for the purposes of this guide, we played Pokemon Alpha Sapphire, so the layout of the area may be a little different, but likely at worst is a mirror of Omega Ruby. After making sure you have the aforementioned moves at your disposal, make your way to Route 128 and dive in any of the large areas outside of the middle land area. Enter the Seafloor Cavern to the south and surface as soon as you get inside.
Head north and upon entering the next room, go north and to the east to find a boulder that you can move to the right into a hole. You will not see a Grunt, in the case of Alpha Sapphire it will be a member of Team Aqua, so challenge him to a battle.
Team Aqua Grunt
-Carvanha – Level 39 (Water/Dark)
-Mightyena – Level 39 (Dark)
After winning that battle, another Grunt can be seen to the right up some stairs, so go ahead and challenge him as well.
Team Aqua Grunt
-Golbat – Level 41 (Poison/Flying)
After this fight, go back to where you fought the first Grunt and head to the northwest exit. This room will feature a number of boulders that need to be cleared out of the way, starting with the first one you see that you need to push to the left and into the hole. The next two boulders in the pathway just need to be pushed one spot east and north respectively to get by, so do so and continue past them.
Destroy the rock you see with Rock Smash, which will actually turn out to be a Graveler that you can fight. Now, work your way back around where you came from. Move to the left side of the boulder that is next to where you smashed the rock and push it right into the hole. After pushing that boulder, do the same to the one to the south. Just like the last room, exit to the room to the northwest.
This will bring to a room full of water with currents to guide you through. Start off by using Surf and then use the north moving currents on the right. Upon stopping, swim to the left and use those north moving currents. After stopping, enter the doorway you see to the right.
Move the first boulder you see to the right, just enough to get by, and go up and fight the Grunt in the way.
Team Aqua Grunt
-Mightyena – Level 38 (Dark)
-Muk – Level 40 (Poison)
After the battle, push the boulder to his left into the hole to its south and then head north to the next room. This next boulder filled room is rather simple, so start by pushing the first two boulders into the respective hole next to each. Now go to the remaining boulder on the bottom right and push it to the left three times. The one directly above needs to be moved down one space, which will let you then push the top right boulder into the hole to its north. After doing so, head through the doorway to the north.
In this new room, follow the only pathway available around in a loop until you see stairs that you can go down. However, do not miss TM26 Earthquake to the southwest before you leave.
This next room is finally the end of the Seafloor Cavern, with you now taking on the leader of Team Aqua or Team Magma, depending on the version you are playing.
Aqua Leader Archie
–Mightyena – Level 41 (Dark)
-Muk – Level 41 (Poison)
-Crobat – Level 41 (Poison/Flying)
-Mega Sharpedo – Level 43 (Water/Dark)
After the battle, Primal Kyogre or Primal Groudon will awaken as disaster has come upon the Hoenn region, leading to the next adventure in Pokemon Omega Ruby and Alpha Sapphire where we will look towards capturing one of the lead legendaries.