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Now get back to Mitonga Island. And go to the lower floor of the village. Then the game shows you a cave. Go into it.
As soon as you enter you see two Pinchers. They say something about a plan and lunches. You have only two minutes to get to their base. For now go east where you see a fork in the path. Go to the north path. Then you have to call Entei to proceed. Go break some rocks and you reach at a fork again. The north one has two larger rocks. The south way has four smaller rocks. At the next fork, if you go south you need Raikou, keep Entei for the North path. Once you reach the other side call Raikou to jump over the crumbling cliffs. Once you reach the small round rocks, be careful as it will crumble if you stay on it for more than 2
seconds. Don't let go of Raikou just yet. Just a little more and you reach a Submarine. The Mission Foil Blue Eyes' Plan begins. Go in, of course.
There is no going back now. Now you will notice that every door has a number written near it, so from now onwards, the doors will be referred with those numbers. So now go into No. 7. And catch that Gligar and Sandslash.
Now go east and you see two doors with No. 6. Go in the top one. And go the upper way and catch that Luxio. Then come back to the entrance and go the other way, you reach a room with another Luxio catch it too. Then get out and go in the other No. 6. and open that Huge Gate. Proceed and you see two pinchers with 2 Gible. And quickly they become 6 Pinchers with a lot of Pokémon. Just you Luck. So get ready to catch 3 Gible and 3 Makuhita. After that go into No. 5.
Then Pichu runs off. Follow it. Break that Gaint Cage. The Pokémon from Dolce Island come out along with your partner's Staraptor. Now back to finding Blue Eyes. Into No. 4. you go and you find Dusclops waiting to teleport you back to the entrance. So go past them and into door 3. There are a lot of angry Pokémon running around so it can be a bit of a challange. Get into the next room to capture 2 Rampardos. Then go ahead to Blue Eyes's room. Be ready to catch Totodile and its evolutions. Feraligatr is a boss Pokémon. After the capture Blue Eyes executes Plan Z and rams the Submarine into the Ocean Floor.
After the cutscene, go up the ladder into the next room. Now you have to get out in 10 minutes. Climb up and avoid the steam. In the next room climb up the left path. And jump off at the top. Then go right and climb. Then jump, climb again to the next room. Climb up the path near the Rampardos. Don't jump anywhere. Climb straight up in the next room. In the next room, climb up then right. The next Room has a Pichu, so you have to find it. Climb then jump, then climb and jump again to get Pichu and then climb tp the top. Catch Furret on the way. Move the Debris out of the way and get to the exit as now you have all the Pichu.
Climb straight up, avoiding the steam. After you rescue Blue Eyes get out.
Back on Land
After you surface, Murph will come on The Union will come and rescue you. And an Excellent Mission Clear. After you land you will find that the Union has a hole in its hull. Also you have to report to Rand.