Latest Pokémon Brilliant Diamond and Shining Pearl patch includes data checker for cloned Pokémon

The patch didn't outright say it, but the illicit modification check is for duplication.

Screengrab via The Pokémon Company

Late last night, a new update for Pokémon Brilliant Diamond and Shining Pearl added features that weren’t available in previous versions of the game, along with bug fixes. However, the information posted in the official patch notes didn’t tell players the whole story about what the update was really doing.

The addition of the Colosseum battle feature and some updates to the Union Room that expand functions were straightforward, but when it comes to the line about Pokémon Trading and Battles, players need to pay close attention.

  • Pokémon Trading and Battles
    • Some Pokémon acquired via unintended methods or illicit modification now cannot be used in Link Trades or Link Battles.

As noted by multiple dataminers within the Pokémon community, version 1.2.0 includes a new “PokeDupeChecker” that specifically checks for clones in the game’s save data in areas like the Party, PC Storage, and Daycare. And, as the line in the update notes, these “clone” Pokémon are then flagged by the game’s internal checker, preventing them from being traded or used in any form of online battle. 

Kaphotics, a prominent dataminer, broke it down further, showing the “is clone” comparison checks go through the standard elements of each Pokémon, including Identification number (PID), encryption constant (EC), Individual values (IVs), Trainer ID, and Nature. There are also independent listings that will ignore special Pokémon like Shedinja and Ninjask, in-game trades, and non-BDSP version IDs.

This check will trigger when loading into the game or opening a trade window, with the flagging process affecting all clones except for one if you have multiple. This essentially creates another post-launch fix for the multiple cloning and duplication glitches that were previously present in the game.

Additionally, some small backend changes were made that might hint at an upcoming update for Pokémon HOME that could include new BDSP support.