There are new legendary Pokémon for you to catch in Pokémon Sword and Shield’s Crown Tundra expansion. The expansion takes you to the snowy area of the Galar region, and it’s full of mysteries for you to unravel and old favorites to encounter, such as the various legendary Pokémon awaiting you. There are a handful of new ones, such as the Galarian versions of Zapdos, Articuno, and Moltres. Some brand new Pokémon are Spectrier and Glastrier, the steeds to the king of Bountiful Harvest, Calyrex.
When you encounter Calyrex, it tells you how the Crown Tundra region once worshipped it and gave it the power it needed to make the crops plentiful. But now that the humans of the region no longer believe in it, Calyrex does not have the same power. However, it has a plan, and you can help it by bringing back the Pokémon’s loyal steed. There are two, Spectrier and Glastrier, and they were once a single Pokémon. Now that they are split off, you have to summon one of them to bring to Calyrex. To summon them, you first need to acquire a special bag of carrot seeds from one of the local villagers at the center of Freezington. After you have them, return to Calyrex, and you now have to pick which one you want to summon.
How to catch Spectirer
Spectirer is the Ghost-type horse Pokémon, so you need to visit the field at the old cemetery that’s to the south of Freezington, right next to the Giant’s Bed.
How to catch Glastrier
Glastrier is the Ice-type horse Pokémon. To summon it, you need to visit the field in the northern section of Snowslide Slope.
Approach the field at these locations and plant the carrot seeds. Calyrex will arrive and double-check with you that you’ve made the correct decision. It will remind you what type of Pokémon it summons by planting the carrot there. If you finalize it, you’ll be able to have Calyrex grow the crop, and you can pull it out from the field.
The chosen horse Pokémon will run by in a cutscene, and you learn from Calyrex that they rode towards Freezington to pillage carrots from the town. You need to head back there to deal with Calyrex’s steed. The horse Pokémon you chose will be waiting in the center of the carrot field in Freezington.
When you approach it in town, the Pokémon attacks you, and you have to battle it. Defeat it in battle, and then it runs off. The horse leaves behind a tuft of its mane, and when you combine it with a flower Calyrex can grow, you can create the Reins of Unity to control the Pokémon once again. After talking with the villager, turn around to find Calyrex and speak to them, and they will grow it for you.
With both of those materials, take it to the mayor in town, the one you learned about the legendary horse Pokémon, and have them make the Reins of Unity. After a bit of dialogue, the mayor would be able to make it, but Peony walks in to save the day and makes it for you.
Once you step outside, Calyrex informs you that the horse Pokémon is resting at the top of the mountain at the Crown Shrine. You need to make your way up to it to use the Reins of Unity. When you arrive to the Crown Shrine, you Calyrex its Reigns of Unity, and they ask you to place the carrot in the basket to summon the horse.
You and Calyrex have to hide after placing the carrot then for the horse to appear. When it does and eats the carrot, Calyrex jumps down on to it and attempts to ride it. The reigns work, and Calyrex once again gains its steed. You now have the opportunity to battle and catch Calyrex with its chosen steed. It will either be a Psychic and Ghost-type or a Psychic and Ice-type, depending on what horse you picked.