8 bit Pokédex

Prior to the 9-bit Pokédex expansion, only 254 species were available at most in the game after the assignment of the Egg to the special case #255.

Replacements

• Added: Leafeon, Glaceon, Sylveon, Togekiss, Weavile, Honchkrow, Mismagius, Electivire, Magmortar, Magnezone, Tangrowth, Rhyperior, Porygon-Z, Yanmega, Gliscor, Mamoswine, and Munchlax.
• Removed: Spearow, Fearow, Lickitung, Goldeen, Seaking, Hoppip, Skiploom, Jumpluff, Aipom, Stantler, Cleffa, Igglybuff, Smoochum, and Delibird.

Pokédex Number Shifts

  ⋮
  Raticate ; #20
- Spearow
- Fearow
+ Marill
+ Azumarill
  Ekans ; #23
  ⋮
  Hitmonchan ; #107
- Lickitung
  Koffing
  ⋮
  Seadra
- Goldeen
- Seaking
+ Togepi
+ Togetic
+ Togekiss
  Staryu ; #120
  ⋮
  Pichu ; #172
- Cleffa
- Igglybuff
- Togepi
- Togetic
+ Munchlax
+ Magnezone
+ Rhyperior
+ Tangrowth
  Natu ; #177
  ⋮
  Bellosom ; #182
- Marill
- Azumarill
  Sudowoodo
  Politoed
- Hoppip
- Skiploom
- Jumpluff
- Aipom
  Sunkern
  Sunflora
  Yanma
+ Yanmega
  Wooper
  ⋮
  Murkrow
+ Honchkrow
  Slowking
  Misdreavus
+ Mismagius
  Unown
  ⋮
  Gligar
+ Gliscor
  Steelix
  ⋮
  Sneasel
+ Weavile
  Teddiursa
  ⋮
  Swinub
  Piloswine
+ Mamoswine
  Corsola ; #222
  Remoraid
  Octillery ; #224
- Delibird
  Mantine
  ⋮
  Porygon2
+ Porygon-Z
- Stantler
  Smeargle
  Tyrogue
  Hitmontop
- Smoochum 
  Elekid
+ Electivire
  Magby
+ Magmortar
  Miltank ; #241
  ⋮
  Celebi ; #251
- (blank)
- (Egg)
- (blank)
- (end) ; #255
+ Leafeon
+ Glaceon
+ Sylveon
+ (Egg & end) ; #255