Prepare to grind
Tera Shards are a new addition to Pokemon Scarlet & Violet tied to the Terastal Forms gimmick. Once you progress far enough into the game, you’ll be able to change any Pokemon’s Tera Type.
Make no mistake, if you want to change a Pokemon’s Tera Type, you are going to have to grind hard. Professional Pokemon battler Wolfey estimates an 8-hour grind to change your entire party’s Tera Types. In other words, you’ve got a long road ahead of you. Here’s what you’ll need to do.
How to change your Pokemon’s Tera Type
Visit the Treasure Eatery in Medali (the spot where you faced off against Normal Type Gym Leader Larry). Then talk to the chef near the back of the restaurant, and exchange 50 shards of the relevant Pokemon type.
Where to get Tera Shards
Fortunately, you’ll get at least a small handful of Tera Shards by exploring. These items can be found on the overworld, so make sure you pick up any glowing spots or Pokeballs that you come across. This is not a reliable way to farm Tera Shards, but it is something to look out for as you complete other objectives.
Your real grind is, like many long term goals in Scarlet & Violet, Tera Raid Battles. Fortunately, the bar to get Tera Shards isn’t as steep as other items. Tera Shards will appear as drops from raid battles starting at 3-star difficulty. Naturally, the harder the Tera Raid, the more Tera Shards you’ll get as a reward. While 6-star Tera Raids will give the best drops, they are also the most intense content to beat. If you can’t reliably defeat 6-Star or 5-Star Raids, there is no shame in sticking with content that you can clear much easier. It’s better to get 10 shards from several raids than to get 0 shards from one you lost.
Tera types matter
Keep in mind that a Tera Raid will only drop shards corresponding to its den. In other words, a Water-Type Tera Raid will only drop Water-Type Tera Shards, regardless of what Pokemon you encountered. If you’re gunning for a specific Tera Type, indiscriminately entering Tera Raids won’t do you much good.
Tera Shards are also a reward from the Academy Ace Tournament that unlocks in the postgame. This is not a reliable way to get Tera Shards, as there’s only a 30% chance of getting it as a reward. Still, the tournament is a decent source of money, so you might as well take the Tera Shards you get from repeating these battles. You’ll need as many as you can find.