Link
There were only 251 Pokemon in the first two generations, so where are the other 5 Pokemon coming from? I'm too lazy to look through it myself at the moment so if someone could explain to me that would be much appreciated
The original new Pokédex was dropped for Pokémon HeartGold and SoulSilver, which alter the Pokémon Gold, Silver, and Crystal order of the Johto Pokédex slightly, moving some Pokémon down the list to add a select few Pokémon that evolve from Generation I and Generation II Pokémon by the method of learning a move (specifically Tangrowth, Mamoswine, Lickilicky, Yanmega, and Ambipom). However, up to #101 (Yanma), the order is the same as that of the new Pokédex, after which it diverges starting with #102 (Yanmega).
Source: The link you shared.
