A battle mechanic introduced in [[Pokemon SV]].

[quote]This phenomenon is found only in the Paldea region and makes Pokémon shine and glimmer like gems.
When a Pokémon Terastallizes, a Tera Jewel appears above the Pokémon’s head like a crown, and the Pokémon’s body glistens like a cut gemstone.
 
All Pokémon in Paldea can Terastallize to gain special powers, and Terastallization allows players to enhance their battle strategies by increasing the power of any moves that have the same type as their Pokémon’s Tera Type. There are 18 types, meaning there are countless combinations of Pokémon and Tera Types.
 
Players can Terastallize a Pokémon once per battle and the transformation will last until the battle ends. Players will need a [[Tera Orb]] to Terastallize a Pokémon, which will need to be recharged after each use. Players can charge their Tera Orb by touching crystals overflowing with Terastal energy or by going to a Pokémon Center.[/quote]
テラスタル