How Many Pokémon Can You Get with Only Pokémon Ruby?
Although the game contains all 386 Pokémon that existed at the time of the game's release, the player can only obtain Pokémon that are part of the Hoenn Pokédex without trading. The Hoenn Pokédex contains 200 Pokémon (202 with Jirachi and Deoxys), meaning a total of 184 Pokémon from the National Dex cannot be obtained. Those 184 are not listed on this page; check out the Locations page to see which Pokémon are excluded.
The number of Pokémon in the Hoenn Pokédex that are available without trading is 177. The list of Pokémon you cannot get without trading, which equals 25 species, is as follows:
- Two Starters (6) - 6 total
- As you can only select one starter Pokémon, the other two starters, and their evolutions, are unavailable; this totals 6 Pokémon.
- Trade Evolutions (6) - 12 total
- Golem, Machamp, Alakazam, Kingdra, Huntail, and Gorebyss evolve by trade. Without the ability to trade, they are unobtainable.
- One Fossil Pokémon (2) - 14 total
- As you can only obtain one Fossil on Route 111, you miss out on the other Fossil Pokémon (Lileep or Anorith) and its evolution.
- Version Exclusives (8) - 22 total
- The following Pokémon cannot be obtained without the use of glitches, trading, or events: Lotad, Lombre, Ludicolo, Sableye, Seviper, Lunatone, Latias, and Kyogre.
- Moon Stone Evolutions (1) - 23 total
- Ruby players can only get one Moon Stone, but two Pokémon require it: Delcatty and Wigglytuff. One of these Pokémon is therefore unobtainable.
- Mythical/Event (2) - 25 total
- Outside of glitches, Jirachi and Deoxys were only obtainable via events that are no longer active, or in Jirachi's case via the Colosseum Bonus Disc (which requires trading).
The Professor Oak challenge guide for Ruby can be found here, although I've made a shorter list of encounters below in case anything happens to the external guide.
Professor Oak Challenge Notes
Pre-Badge 1 (Roxanne) - 37 Total Pokémon
- Gift on Route 101: One starter & its evolutions (3 total)
- Walking on Route 101: Zigzagoon, Linoone (5 total)
- Walking on Route 101: Poochyena, Mightyena (7 total)
- Walking on Route 101: Wurmple, Silcoon, Beautifly, Cascoon, Dustox (12 total) (alternatively, catch Silcoon and Cascoon in Petalburg Woods)
- Walking on Route 103: Wingull, Pelipper (14 total)
- Walking on Route 102: Ralts, Kirlia, Gardevoir (17 total)
- Walking on Route 102: Surskit, Masquerain (19 total)
- Walking on Route 102: Seedot, Nuzleaf (21 total)
- Walking on Route 104: Taillow, Swellow (23 total)
- Walking in Petalburg Woods: Shroomish, Breloom (25 total)
- Walking in Petalburg Woods: Slakoth, Vigoroth, Slaking (28 total)
- In-game Trade in Rustboro City: Makuhita, Hariyama: Trade your Slakoth (30 total)
- Walking on Route 116: Skitty (31 total)
- Walking on Route 116: Whismur, Loudred, Exploud (34 total)
- Walking on Route 116: Nincada, Ninjask, Shedinja (37 total)
Badge 1 through Badge 2 (Wattson) - 67 Total Pokémon
- Fishing (Old Rod) in Dewford Town: Magikarp, Gyarados (39 total)
- Fishing (Old Rod) in Dewford Town: Tentacool, Tentacruel (41 total)
- Fishing (Old Rod) in Petalburg City: Goldeen, Seaking (43 total)
- Walking in Granite Cave (all areas): Zubat, Golbat, Crobat (46 total)
- Walking in Granite Cave (all areas): Abra, Kadabra (48 total)
- Walking in Granite Cave 1F: Geodude, Graveler (50 total)
- Walking in Granite Cave B1F, B2F, and Steven's room: Aron, Lairon, Aggron (53 total)
- Walking in Granite Cave B1F and B2F: Mawile (54 total)
- Walking on Route 110: Plusle (55 total)
- Walking on Route 110: Minun (56 total)
- Walking on Route 110: Electrike, Manectric (58 total)
- Walking on Route 110: Gulpin, Swalot (60 total)
- Walking on Route 110: Oddish, Gloom (62 total)
- Walking on Route 117: Volbeat (63 total)
- Walking on Route 117: Illumise (64 total)
- Walking on Route 117: Marill, Azumarill (66 total)
- Walking on Route 117: Roselia (67 total)
Badge 2 through Badge 3 (Flannery) - 93 Total Pokémon
- Rock Smash in Granite Cave B2F: Nosepass (68 total)
- Walking on Route 112: Numel, Camerupt (70 total)
- Walking on Route 112: Machop, Machoke (72 total)
- Walking in Fiery Path: Grimer, Muk (74 total)
- Walking in Fiery Path: Koffing, Weezing (76 total)
- Walking in Fiery Path: Slugma, Magcargo (78 total)
- Walking in Fiery Path: Torkoal (79 total)
- Walking on Route 113: Spinda (80 total)
- Walking on Route 113: Skarmory (81 total)
- Walking on Route 113: Sandshrew, Sandslash (83 total)
- Walking on Route 114: Swablu, Altaria (85 total)
- Walking on Route 114: Zangoose (86 total)
- Walking in Meteor Falls (all areas): Solrock (87 total)
- Evolve Skitty with a Moon Stone from Meteor Falls (88 total)
- Evolve Gloom with a Sun Stone stolen from, or captured on, wild Solrock from Meteor Falls (89 total)
- Walking in Jagged Pass: Spoink, Grumpig (91 total)
- Gift (Egg) in Lavaridge Town: Wynaut, Wobbuffet (93 total)
Badge 3 through Badge 5 (Norman) - 102 Total Pokémon
- Walking on Route 111: Trapinch, Vibrava, Flygon (96 total)
- Walking on Route 111: Cacnea, Cacturne (98 total)
- Walking on Route 111: Baltoy, Claydol (100 total)
- Revive the Root or Claw Fossil in Rustboro City: One of Lileep or Anorith, and its evolution (102 total)
Badges 5 through 6 (Tate & Liza) - 159 Total Pokémon
- Walking on Route 115: Jigglypuff (103 total)
- Walking in New Mauville (both floors): Magnemite, Magneton (105 total)
- Walking in New Mauville (both floors): Voltorb, Electrode (107 total)
- Fishing (Good Rod) in Petalburg City: Corphish, Crawdaunt (109 total)
- Fishing (Good Rod) in Dewford Town: Wailmer, Wailord (111 total)
- Fishing (Good Rod) on Route 111: Barboach, Whiscash (113 total)
- Fishing (Good Rod) on Route 118: Carvanha, Sharpedo (115 total)
- Walking on Route 118: Kecleon (116 total) (alternatively, use the Devon Scope on Kecleon on Routes 119 and 120)
- Walking on Route 119: Tropius (117 total)
- Evolve one Leaf Stone Pokémon with a Leaf Stone from Route 119 (118 total)
- Fishing (any Rod) on Route 119: Feebas, Milotic (120 total) (you probably want to make Pokéblocks in Lilycove City, though)
- Gift in the Weather Institute: Castform (121 total)
- Walking on Route 120: Absol (122 total)
- Walking in Mt. Pyre (all areas): Duskull, Dusclops (124 total)
- Walking in Mt. Pyre Inside 4F, 5F, and 6F and Summit: Shuppet, Banette (126 total)
- Walking in Mt. Pyre Outside: Vulpix, Ninetales (128 total)
- Walking in Mt. Pyre Outside: Meditite, Medicham (130 total)
- Walking in Mt. Pyre Summit: Chimecho (131 total)
- Walking in the Safari Zone Areas 1 and 2: Girafarig (132 total)
- Walking in the Safari Zone Areas 1, 2, and 4: Natu, Xatu (134 total)
- Walking in the Safari Zone Areas 1, 2, and 3: Doduo, Dodrio (136 total)
- Walking in the Safari Zone Areas 1 and 2: Pikachu, Raichu (138 total)
- Walking in the Safari Zone Area 3: Rhyhorn, Rhydon (140 total)
- Walking in the Safari Zone Area 3: Pinsir (141 total)
- Walking in the Safari Zone Area 4: Phanpy, Donphan (143 total)
- Walking in the Safari Zone Area 4: Heracross (144 total)
- Surfing in the Safari Zone Areas 2 and 3: Psyduck, Golduck (146 total)
- Route 117: Breed Jigglypuff to get Igglybuff (147 total)
- Route 117: Breed Marill or Azumarill to get Azurill (148 total)
- Route 117: Breed Pikachu or Raichu to get Pichu (149 total)
- Walking or Surfing in Shoal Cave (all areas): Spheal, Sealeo, Walrein (152 total)
- Walking in Shoal Cave (Ice room during low tide): Snorunt, Glalie (154 total)
- Fishing (Super Rod) in Lilycove City: Staryu (155 total)
- Fishing (Super Rod) in Ever Grande City: Luvdisc (156 total)
- Fishing (Super Rod) in Ever Grande City: Corsola (157 total)
- Fishing (Super Rod) on Route 132: Horsea, Seadra (159 total)
Badges 6 through 7 (Wallace) - 168 Total Pokémon
- Underwater on Route 126: Clamperl (160 total)
- Underwater on Route 126: Chinchou, Lanturn (162 total)
- Underwater on Route 126: Relicanth (163 total)
- Evolve Staryu with a Water Stone from the Treasure Hunter on Route 124 (164 total)
- Evolve one Leaf Stone Pokémon with a Leaf Stone from the Treasure Hunter on Route 124 (165 total)
- Static encounter in Desert Ruins: Regirock (166 total)
- Static encounter in Island Cave: Regice (167 total)
- Static encounter in the Cave of Origin: Groudon (168 total)
Badges 7 through 8 (Winona) - 171 Total Pokémon
- Walking in Meteor Falls B1F back: Bagon, Shelgon, Salamence (171 total)
Badge 8 through Elite Four - 172 Total Pokémon
Post-Elite Four - 177 Total Pokémon
- Gift in Mossdeep City: Beldum, Metang, Metagross (175 total)
- Static encounter in Sky Pillar: Rayquaza (176 total)
- Roaming Legend: Latios (177 total)