The three Regi are Regirock, Regice and Registeel. These legendary golems can help you a lot in the final part of the game, because you can catch them before taking on the Pokemon League. Obtaining all three will take time and you will have to embark on a journey that will take you through the entire Hoenn region.
Steps
Part 1 of 7: Preparations
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Step 1. Form a team with Pokemon that know the Dig, Surf and Sub moves
These three techniques are essential to unlock the Regi. You can get Pit from the Fossil Expert's brother on Route 114. You will receive HM03 (Surf) after defeating Norman, the Petal City Gym Leader. You can get Subs from Steven in Greenbeard.
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Step 2. Defeat the seventh gym leader
To get all the moves you need to capture the Regi, you must have beaten at least the top seven Gym Leaders. After defeating Tell & Pat in Greenbone City, you will have the option to use Sub in deep water. This is the last skill needed to unlock the Regi.
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Step 3. Capture a Relicanth
This rare Pokemon can only be found in underwater areas. In Ruby and Sapphire, you can use Sub on Routes 124 and 126 to encounter a Relicanth, which has 5% spawn as a random enemy. In Alpha Sapphire and Omega Ruby, you can find additional underwater areas on Routes 107, 129 and 130. There are also many underwater areas around the world.
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Step 4. Capture or get a Wailord thanks to an evolution
You can fish a Wailmer in many areas of the game. Once it gets to level 40, the Pokemon will evolve into Wailord. You can also try to catch a Wailord by swimming on Route 129, but the chance of it appearing as a random enemy is only 1%.
Part 2 of 7: Swim along the Currents
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Step 1. Reach Orocea
It is the best place to start swimming. If you don't choose the right currents, you can fly back to Orocea and try again.
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Step 2. Swim west of Orocea
You will reach Route 132.
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Step 3. Disembark on the island to the south
Cross it on foot and enter the water again at the point where the seabed is low, to the southwest.
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Step 4. Continue west until you reach the next shallow area
Walk to the western shore of the island. Make sure you are at least three steps below the upper edge of the island and at least three steps above the lower shore.
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Step 5. Swim west of the island
The current should pull you directly into a section with deep water, where you can use Sub.
Part 3 of 7: Unlocking the Regi
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Step 1. Find the deep water spot and use Sub
You can find it in the lower right corner of Route 134, surrounded by six rocks.
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Step 2. Continue south into the cave until you reach the plate with Braille inscriptions
You'll find it on the other side of a circular tunnel in the underwater cave.
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Step 3. Use Sub in front of the plate
You will emerge in the Engraved Room.
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Step 4. Find the Braille inscription plate on the back wall of the cave
There is a lot of Braille writing in the cave, but you have to look for the one along the back wall. It reads "USE DIT HERE".
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Step 5. Use Fossa in front of the slab
Walk into the square in front of it and turn your character against the wall. Use the Pit command. A door will appear in the rock.
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Step 6. Put Relicanth as the first Pokemon in the group and Wailord as the last
Use the squad screen to rearrange your Pokemon.
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Step 7. Examine the slab on the back wall of the second cave
With Relicanth as the first Pokemon in the group and Wailord as the last, you will unleash an earthquake. This indicates that the doors to the Island Grotto, the Sandy Ruins and the Ancient Tomb have been opened. By visiting those places, you can capture the three Regi.
Part 4 of 7: Finding Regice
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Step 1. Prepare your team
Regice is a level 40 Pokemon, but it is recommended that your party members be level 50 to have a chance of winning. One of the most common tactics to weaken Regice without defeating him is to use a Pokemon that knows the False Swipe move. It allows you to reduce the enemy's health by up to 1 HP without knocking them out. Another common strategy is to fall asleep or paralyze the opponent to be captured. This increases the chances of getting the Pokemon.
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Step 2. Stock up on Ultra Balls
It is the Poké Balls that have the greatest chance of catching Regice. Depending on your opponent's health and the negative states affecting him, you may need a lot of orbs.
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Step 3. Reach Route 105
The Island Cave on the west section of the route should be accessible. Enter the cave.
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Step 4. Read the inscription and wait
The Braille text asks to wait twice; to do this, you have to stay still for two minutes. Leave the console on the table for 120 seconds to avoid moving the character by mistake. If you make any unwanted movements, exit the cave and try again. After two minutes, a door will open.
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Step 5. Save the game
You only have one chance to take on Regice, so be sure to save before starting the fight. This way, you will be able to charge the game if you inadvertently KO your opponent before capturing him or if you are defeated.
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Step 6. Capture Regice
Approach the Pokemon and the fight begins. Reduce his health, you can try to put him to sleep or paralyze him. When Regice's health is red and the Pokemon is asleep or frozen, it begins throwing Ultra Ball.
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Step 7. Give Regice a nickname (Alpha Sapphire and Omega Ruby)
If you want to catch Regigigas, your Regice must have a nickname. You can assign one to him at the time of capture, or take the Pokemon to the Nameday Judge to give him a new one. You can find the judge south of the Arena delle Virtù in Porto Selcepoli.
Part 5 of 7: Finding Regirock
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Step 1. Add a Pokemon that knows the Strength move to your team
This technique is required to reach Regirock.
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Step 2. Prepare for Regirock
Like the other Regi, Regirock is a level 40 Pokemon. Assemble a team with Water-type Pokemon to deliver effective hits. Also include a Pokemon that can put Regirock to sleep or paralyze, as well as a monster that knows False Swipe. Finally, be sure to stock up on Ultra Balls.
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Step 3. Reach Route 111
You will find the Sandy Ruins in the east section of the path.
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Step 4. Read the inscription on the back wall of the cave
The signs in Braille explain what you need to do to reach Regirock.
- Walk two steps to the right and two steps down.
- Use Force in that spot and a door will appear.
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Step 5. Save the game
You only have one chance to face Regirock, so remember to save before approaching. This way, if something goes wrong, you can load the game and try again.
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Step 6. Regirock capture
The fight begins. Use Water-type Pokemon to reduce your opponent's health, then use False Swipe to weaken them as much as possible without defeating them. Hit Regirock with Sleep or Paralysis, then start throwing Ultra Balls to catch him.
Part 6 of 7: Finding Registeel
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Step 1. Add a Pokemon that knows the Fly move to your team
You will need that technique to open the door that leads to Registeel.
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Step 2. Prepare to face Registeel
Like the other two Regi, the latter is also a legendary Pokemon of level 40. Its type is Steel, which is why it is not easy to inflict damage on it. Assemble a team with Fighting, Ground or Fire-type Pokemon. Also bring a monster that knows False Swipe, a move that will allow you to minimize Registeel's health without defeating him. To make it easier to catch, add a Pokemon that knows Sleep or Paralysis to the party. Don't forget the Ultra Balls!
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Step 3. Reach Route 120
The entrance to the Ancient Tomb is located in the west section of the route.
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Step 4. Read the inscription and go to the center of the room
The Braille text offers hints for dealing with Registeel.
- Move your character to the center of the cave.
- Use the Fly move to open the door.
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Step 5. Save before fighting
You only have one chance to catch Registeel, so be sure to save your game right before the fight. This way, you'll be able to load a previous save and try again, should you inadvertently defeat the Pokemon.
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Step 6. Capture Registeel
At the start of the fight, quickly reduce the enemy's health with Fighting, Ground, and Fire-type moves. Use False Swipe to lower Registeel's HP further without defeating him. When his health bar is red, put him to sleep or paralyze him, then start trying to catch him by throwing Ultra Balls.
Part 7 of 7: Obtaining Regigigas (Alpha Sapphire and Omega Ruby)
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Step 1. Defeat Groudon or Kryogre
You cannot face Regigigas before defeating the legendary pokemon that brings destruction in your version of the game.
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Step 2. Make sure you've already captured the three legendary golems
To take on Regigigas, Regirock, Registeel and Regice must be on your team.
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Step 3. Give Regice a nickname
If you didn't choose one at the time of catching the Pokemon, go to Porto Selcepoli and talk to the Onomastic Judge. You can give Regice any name you like, as long as it's not the original one.
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Step 4. Have Regice hold a "cold" object
He will have to hold a Snowball, a Cold Rock, a Gelomai or a Conostropolis.
- You can win Snowballs in the Battle Mansion or find them on wild Snorunts;
- You can find the Cold Rocks at the Weather Institute;
- You can find the Gelomai in the Wave Cave;
- You can win Conostropolis in the Arena of Virtues, or buy them in Cyclamen City if you have Regice in your team.
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Step 5. Reach the Island Cave on Route 105
This is the cave where you captured Regice. Make sure you go there during the day, as Regigigas doesn't show up at night.
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Step 6. Save your game before entering the cave
If you meet the requirements, the fight will begin as soon as you enter the cave. Save before fighting, because you only have one chance to capture Regigigas.
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Step 7. Capture Regigigas
Unlike other golems, Regigigas is level 50, so the fight will be more challenging. He is weak to Fighting-type moves, so use them to reduce his health. When the enemy is nearly KO'd, use False Swipe to further lower their HP without defeating them. After weakening it, throw Ultra Balls to try and catch it.