How to Get Thundurus - Pokémon Legends: Arceus
First, you have to head to the galaxy hall to learn more about the powers of nature.
Accept request 94. You must incarnate forces for hisui.
You will need to reach the sand's reach when the weather is a thunderstorm.
Thundurus will spawn in this condition.
In order to catch Thundurus, its tornado barrier must be dealt with first.
Thundurus can be found only at sea, so you need to use the Basculegion mount to chase it.
You have to swim up to Thundurus quickly while dodging its attacks. Do your best to get around it.
When its barrier is down, throw a ball of mud or an Apricorn at thundurus to stun it.
You have to make a back strike with your pokemon to begin the battle, after stunning it.
As you lower its health, the HP gauge turns yellow. Now you must throw an ultra ball at it.
Thundurus is weak to rock and ice moves. Pokemon who have those types of moves will lower Thundurus's HP more quickly.