From Bulbapedia, the community-driven Pokémon encyclopedia.
This is a list of Pokémon by the items they may be holding when encountered in the wild in Generation II, or when obtained in Generation I and traded to Generation II.
Generation I held items
In the Generation I games, there are no held items; however, Pokémon are holding an item by default when traded to a Generation II game. These items are determined by a value in the Pokémon data structure that has no effect in Generation I, and is set to that species's catch rate upon obtaining it. Therefore, a given Pokémon's catch rate translates into the item it will be holding by default when traded to Generation II. Because this value is set when the Pokémon is obtained, it does not change when a Pokémon evolves, so its held item depends on the evolutionary stage at which it was obtained.
Four species of Pokémon have different held items when traded to Generation II depending on whether they were caught in Pokémon Red and Blue (Pokémon Red, Green, and Blue in Japan) or Pokémon Yellow.
- The starter Pikachu's held item value is specially set to 163 (as opposed to Pikachu's regular catch rate of 190) when it is obtained, which causes it to hold a Light Ball when traded over.
- A wild Kadabra's held item value is set to 96 upon capture (as opposed to 100), which gives it a TwistedSpoon when traded over.
- Dragonair and Dragonite's actual catch rates are different, having been changed to 27 and 9 respectively in Pokémon Yellow, relative to previous games. Consequently, Dragonair caught in Pokémon Yellow will hold a Protein (index number 27) in Generation II, and wild Dragonite caught in Pokémon Yellow will hold an Antidote (index number 9) in Generation II; however, wild Dragonite do not appear in Pokémon Yellow, so the change to Dragonite's catch rate normally has no effect.
Gift Pokémon from Pokémon Stadium also have their held item set to a value other than their catch rate. The Pokémon obtained for clearing the Gym Leader Castle have their held item set to the Normal Box or Gorgeous Box, depending on whether it was cleared as Round 1 or Round 2. The Amnesia Psyduck has its held item set to the Normal Box.
Some catch rate values do not directly correlate into an item when traded. Instead, they correspond to Teru-sama, other glitch items, or Key Items. To compensate for this, the given value is converted into an entirely different number when traded to Generation II.
Items held in Generation II (including holding no item) will be conserved when traded to Generation I and will not be changed back to the Generation I item.
Because items are only set when a Pokémon is caught, evolving it does not change the held item. The "Gen I" header below contains data for held items the Pokémon would possess if it were caught in the wild without any evolution involved.
Generation II held items
Wild Pokémon in Generation II games can have no item (at a 75% chance) or hold a common item (approximately a 23% chance) or a rare item (approximately a 2% chance). When a Pokémon is encountered, there is a 192/256 chance that it will have no item, based on a randomly generated 8-bit value. If it will have a held item, a second random 8-bit value decides which item it will hold, with a 21/256 chance it will hold its rarer item.
Some Pokémon, such as Dragonite, have held items defined but cannot actually be found in the wild.
A Pokémon can be forced to hold its common item if a special flag is set for the encounter. This is used for Ho-Oh in Tin Tower and Snorlax in Vermilion City; it is also used for Lugia in Whirl Islands, but Lugia has no held items defined.
Held item table