Letter is an item in the “Plot advancement” category (Key Items).
In-game descriptions
| Ruby / Sapphire · Emerald | A letter to STEVEN from the PRESIDENT of the DEVON CORP. |
|---|---|
| FireRed / LeafGreen | An extremely important letter to STEVEN from the PRESIDENT of the DEVON CORPORATION. |
| Sun / Moon · Ultra Sun / Ultra Moon | An extremely important letter to Steven from the President of Devon Corporation. |
| Let’s Go, Pikachu! / Let’s Go, Eevee! · Sword / Shield | An extremely important letter to Steven from the president of Devon Corporation. |
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