Time Travel Penalty
If the Generation 4 Pokémon games detect you changing your system time, a 24-hour timer is initiated and penalties will be applied to your game. This 24-hour penalty timer is impacted by the timer bug.
The games detect time travel in two ways:
- By comparing your system’s RTC offset against the RTC offset stored in your previous save file
- By comparing your system’s MAC address against the MAC address stored in your previous save file
While the penalty timer is active, the following mechanics are impacted:
Special Dates
The benefits of playing on special dates that impact egg hatching or encounter rates are not applied.
Weather
In Generation 4, certain dates can cause specific areas to have different weather. If the penalty timer is active in Diamond, Pearl, or Platinum, the game sets the weather at all of these locations to the weather present on January 1st. If you’re being penalized in HeartGold/SoulSilver, you’ll get regular hail instead of Diamond Dust at Mt. Silver.
Berries and Honey Trees
Berries and Honey Trees can still progress under penalty, but any progress that would have been made while time traveling is not applied.
Underground
If the penalty timer is active, you cannot trade goods in the underground with other players.
Apriblender
Under normal circumstances, every day that passes increases your juice’s mildness value by 10, up to a maximum of 255. However, if the game detects you time traveled for this, the mildness will not change. Taking steps will still impact mildness.
Pal Park
If Sinnoh’s Pal Park detects time traveling, you are locked out of using the Pal Park for 24 hours. You might only be locked out of trading with a specific game for those 24 hours; additionally, I was not able to confirm if the Pal Park uses the same 24-hour penalty timer system as the other mechanics. It does, however, perform the same checks of your MAC address and RTC offset.
Johto Safari Zone
If your penalty timer is active, the day counters in your Safari Zone areas will not progress.