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Here is the new numbering system seen in Ruby/Sapphire. These are for the Pokémon which are unobtainable in R/S:

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#203 Bulbasaur - #204 Ivysaur - #205 Venusaur

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#206 Charmander - #205 Charmeleon - #206 Charizard

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#209 Squirtle - #210 Wartortle - #211 Blastoise

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#212 Caterpie - #213 Metapod - #214 Butterfree

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#215 Weedle - #216 Kakuna - #217 Beedrill

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#218 Pidgey - #219 Pidgeotto - #220 Pidgeot

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#221 Rattata - #222 Raticate

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#223 Spearow - #224 Fearow

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#225 Ekans - #226 Arbok

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#227 Nidoran - #228 Nidorina - #229 Nidoqueen

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#230 Nidoran - #231 Nidorino - #232 Nidoking

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#233 Clefairy - #234 Clefable

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#235 Paras - #236 Parasect

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#237 Venonat - #238 Venomoth

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#239 Diglett - #240 Dugtrio

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#241 Meowth - #242 Persian

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#243 Mankey - #244 Primeape

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#245 Growlithe - #246 Arcanine

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#247 Poliwag - #248 Poliwhirl - #250 Poliwrath

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#250 Bellsprout - #251 Weepinbell - #252 Victreebel

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#253 Ponyta - #254 Rapidash

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#255 Slowpoke - #256 Slowbro


#257 Farfetch'd

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#258 Seel - #259 Dewgong

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#260 Shellder - #261 Cloyster

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#262 Gastly - #263 Haunter - #264 Gengar


#265 Onix

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#266 Drowzee - #267 Hypno

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#268 Krabby - #269 Kingler

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#270 Exeggcute - #271 Exeggutor

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#272 Cubone - #273 Marowak

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#274 Hitmonlee / #275 Hitmonchan


#276 Lickitung


#277 Chansey


#278 Tangela


#279 Kangaskahn


#280 Mr. Mime


#281 Scyther


#282 Jynx


#283 Electabuzz


#284 Magmar


#285 Tauros


#286 Lapras


#287 Ditto

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#288 Eevee - #289 Vaporeon / #290 Jolteon / #291 Flareon


#292 Porygon

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#293 Omanyte - #294 Omastar

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#295 Kabuto - #296 Kabutops


#297 Aerodactyl


#298 Snorlax


#299 Articuno


#300 Zapdos


#301 Moltres

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#302 Dratini - #303 Dragonair - #304 Dragonite


#305 Mewtwo


#306 Mew

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#307 Chikorita - #308 Bayleef - #309 Meganium

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#310 Cyndaquil - #311 Quilava - #312 Typhlosion

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#313 Totodile - #314 Croconaw - #315 Feraligatr

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#316 Sentret - #317 Furret

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#318 Hoothoot - #319 Noctowl

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#320 Ledyba - #321 Ledian

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#322 Spinarak - #323 Ariados


#324 Cleffa

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#325 Togepi - #326 Togetic

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#327 Mareep - #328 Flaaffy - #329 Ampharos


#330 Sudowoodo


#331 Politoed

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#332 Hoppip - #333 Skiploom - #334 Jumpluff


#335 Aipom

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#336 Sunkern - #337 Sunflora


#338 Yanma

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#339 Wooper - #340 Quagsire

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#341 Espeon / #342 Umbreon


#343 Murkrow


#344 Slowking


#345 Misdreavus


#346 Unown

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#347 Pineco - #348 Forretress


#349 Dunsparce


#350 Gligar


#351 Steelix

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#352 Snubbull - #353 Granbull


#354 Qwilfish


#355 Scizor


#356 Shuckle


#357 Sneasel

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#358 Teddiursa - #359 Ursaring

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#360 Swinub - #361 Piloswine

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#362 Remoraid - #363 Octillery


#364 Delibird


#365 Mantine

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#366 Houndour - #367 Houndoom


#368 Porygon2


#369 Stantler


#370 Smeargle

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#371 Tyrogue - #372 Hitmontop


#373 Smoochum


#374 Elekid


#375 Magby


#376 Miltank


#377 Blissey


#378 Raikou


#379 Entei


#380 Suicune

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#381 Larvitar - #382 Pupitar - #383 Tyranitar


#384 Lugia


#385 Ho-oh


#386 Celebi

Pokémon Obtainable in Game