Trade

A trade occurs when two trainers exchange Pokémon. Trades can be conducted either with a trade machine (player to player) or using traders (player to NPC). Trading causes happiness to be reset to 70, but no other aspects of the traded Pokémon are affected. Unlike in the Pokémon games, traded Pokémon do not gain boosted experience and have no chance of disobeying their new owners regardless of their levels.

Evolution

A good amount of Pokémon only evolve when traded. The majority of these Pokémon are unavailable legitimately in single player, although Machamp, Golem, Gengar, Steelix and Gigalith can be obtained as traders may potentially offer them or their pre-evolutions.

• Kadabra→Alakazam
• Machoke→Machamp
• Graveler→Golem
• Haunter→Gengar
• Boldore→Gigalith
• Gurdurr→Conkeldurr
• Phantump→Trevenant
• Pumpkaboo→Gourgeist

Some evolutions require that the Pokémon be traded for a specific Pokémon to evolve.

• Karrablast→Escavalier (Shelmet)
• Shelmet→Accelgor (Karrablast)

Some evolutions also require that the Pokémon is holding a specific held item.

• Poliwhirl→Politoed (King's Rock)
• Slowpoke→Slowking (King's Rock)
• Onix→Steelix (Metal Coat)
• Rhydon→Rhyperior (Protector)
• Seadra→Kingdra (Dragon Scale)
• Scyther→Scizor (Metal Coat)
• Electabuzz→Electivire (Electirizer)
• Magmar→Magmortar (Magmarizer)
• Porygon→Porygon2 (Up-Grade)
• Porygon2→Porygon-Z (Dubious Disc)
• Clamperl→Huntail (Deep Sea Tooth)
• Clamperl→Gorebyss (Deep Sea Scale)
• Dusclops→Dusknoir (Reaper Cloth)
• Spritzee→Aromatisse (Sachet)
• Swirlix→Slurpuff (Whipped Dream)