TR30 is an item in the “All machines” category (TMs and HMs). It costs ₽4000.
In-game descriptions
| Sword / Shield | The user compels the target to keep using the move it encored for three turns. |
|---|
Move taught
| Sword / Shield | Encore |
|---|
Where to find it
Not placed on the atlas maps (so far: Red/Blue and Generation 3).
Sources : PokeAPI (items, item_flavor_text, machines) · atlas · pokeemerald species_info.h