From PokéHeroes Wiki
Retro Pokemon are Pokemon with Gen 1-3 sprites. They are not breedable.
Obtaining Retro Pokémon
Not all the Retro Pokémon are obtainable currently, but some can be obtained by purchasing Premium-ship.
- - Retro Bulbasaur, Retro Charmander, and Retro Squirtle can be obtained as vouchers when purchasing 1 Month + Premium Ship.
- - Retro Pikachu was an event Pokemon obtainable from 22/Jul/2013 to 28/Jul/2013. It was then made obtainable again during the Retro Pikachu Event through the Yellow Forest.
- - Retro Magikarp is currently only once obtainable as a gift from Prof. Rowan for helping him in a quest.
- - Retro Mew can be obtained as a voucher when purchasing 1 year Premium-ship.
- - Retro Chikorita, Retro Cyndaquil, Retro Totodile, Retro Sentret and Retro Hoothoot can be obtained as daily rewards from the Contentration Game.
- - Retro Togepi can be obtained from the Daycare. After adopting 500 eggs from the daycare, the owner will ask you if you would like to take care of a mysterious egg. You can get another Retro Togepi for every 500 eggs you adopt form the Daycare.
- - Retro Delibird was rarely obtainable through Christmas gifts during the Advent time. [2013 / 2014 / 2015]
- - Retro Poochyena, Retro Zigzagoon, and Retro Taillow was obtained during 'Month of Hoenn', from 18/01/14 to 31/01/14. It was then made obtainable again during the ORAS Event through the Route 102 Rumble Area.