Koraidon and Miraidon are the box legendaries of Pokémon Scarlet and Violet, but unlike some of the other legendary Pokémon in the franchise, you get to use these Pokémon in a different way. Older fans of the franchise will remember the sudden encounter with a legendary Pokémon leading up to an intense battle as you attempt to catch them. However, Pokémon Scarlet and Violet let you use the instantly iconic Koraidon and Miraidon in a different way. (Spoilers for Scarlet and Violet’s endgame!)
Throughout Pokémon Scarlet and Violet, depending on which game you get, you will bond with the legendary Pokémon as they function as your ride Pokémon. Koraidon and Miraidon have different forms, a “battle form” and a form where they simply function as your ride Pokémon. They will take you around Paldea, help you climb mountains, and allow you to swim across rivers and oceans. Eventually, you will be able to use these Pokémon in battle.
How to get Koraidon and Miraidon’s battle mode
After completing all three main story arcs, you will start a hidden fourth arc as you trek into Area Zero. Long story short, the final climactic battle sees you battling an AI Professor, who will lock all of your Pokémon. However, your Koraidon and Miraidon are registered under the professor, and this will allow you to send them out into battle in a climactic fight against their own Koraidon or Miraidon.
After beating the professor and essentially completing the game, Koraidon and Miraidon will be available for you to use in battle. Head to the menu and scroll over to the six Pokémon slots on the left side of the screen. From here, scroll down to your ride Pokémon, and click them. It will ask you if you want to change Koraidon or Miraidon to its battle form. You will need an empty slot in your party, and this will allow you to use them in battle.
Unfortunately, this will also cause you to lose your ride Pokémon slot. You cannot ride Koraidon and Miraidon and use them in a battle at the same time. Fortunately, you can catch another Koraidon and Miraidon in Area Zero.