During your research within the Galaxy Group, you will have to help the guardians of the Diamond and Pearl clans by calming the Kings and Queens of each zone. The so-called Monarchs are the bosses of Pokémon Legends Arceus and you have surely noticed it, but the fight against them is not quite the same as for the other creatures. Even if they are not quite Monarchs, we will dwell on Palkia and Dialga in their original form.
Dialga and Palkia, the Espace Temps duo
These legendary Pokémon form the sixth boss. Indeed, depending on your choice of partner when searching for Truth, Knowledge and Courage lakes, you will have to face Dialga or Palkia. Don't worry, you'll still have the two creatures to capture in the end. In addition, their attacks are the same so even if this guide will be based on Dialga at the level of the images, you will have the information for the two bosses.
As you could see with Giratina in Platinum, these two are entitled to their Original form in LPA. Let's now discover their attacks.
First attack
The first attack is simply Draco Meteor. An area appears on the ground and a meteor falls on the area. To dodge it, simply get out of the impact area. A second version will arrive later where the meteors will fall on a whole line and no longer in one place. Be careful because after the impact on the ground, the area will do damage to you if you go there because of the flames.
second attack
The second attack consists of three shock waves that must be dodged by rolling over them.
Defeat Dialga or Palkia
For this fight, you will need to have the other legendary in your team and then return to the Temple of Sinnoh. After the cutscene, the fight begins and unlike the previous bosses, it will not be possible to stun it and therefore launch your Pokémon to lower its gauge faster. Rest assured, the confrontation will be rather easy since you will just have to dodge his attacks by throwing your pacifying bombs. His gauge will go down pretty quickly and once beaten, you'll capture him in the Origin Ball which looks a lot like the Memory Ball. Lo and behold, you saved Hisui from a terrible threat and you captured the two legendaries. However, your adventure is far from over.
Note that to have access to their original form, it will be necessary to obtain the Pearl and Adamant Globes by doing the quests "The Treasure of the Pearl Clan" and "The Treasure of the Diamond Clan" which are available after completing the story.