Out of all the games in the Pokémon series, important changes from other Pokémon games. The next games in the series, Pokémon Scarlet and Violet, will hopefully follow in its footsteps when they release on November 18.
The Pokédex is a digital encyclopedia containing information on every Pokémon in existence. Every generation of games has its own model, most of them taking the form of a small handheld device similar to a PDA in early iterations. Over the years, it's become more and more streamlined, and the latest versions are similar to smartphones. In the games, players have to either capture a Pokémon or evolve it from a previous form in order to fill out its entry in the Pokédex. This differs from the anime, where the information already comes preloaded. Completing the Pokédex in its entirety is one of players' main goals in Pokémon's mainline series games, and the primary goal of Pokémon Legends: Arceus.
The reason why Pokémon Legends: Arceus' Pokédex is so much better than other games' is because players are actually able to complete it by themselves, which isn't possible in other games. Due to version-exclusive Pokémon, those that only evolve when traded, and the fact that there's no way to obtain all three starters without trading, players will have to trade with others via online features if they want to complete the Pokédex in most games. This can be very frustrating and will hopefully be left behind in the Pokémon mainline series' future. Sadly, version exclusives have been confirmed for Gen 9, meaning that Pokémon SV won't be helping the series' problem with the Pokédex, but there's still a chance that Gen 10 will make completing it solo possible in the mainline series.
Pokémon Legends: Arceus Does The Pokédex Right
Pokémon Legends: Arceus doesn't have a counterpart version, meaning players can find every Pokémon in the game without having to trade. Its Pokédex also outshines those in the mainline series with the small challenges that players complete in order to fill out its entries, instead of just catching the Pokémon and being finished. This can be something of a grind, but it's still very fun, and adds to the replayability. It also motivates players to explore and interact with PLA's semi-open world more than they might have if they were able to complete the Pokédex more easily.
It seems unlikely that future entries in Pokémon's mainline series will bring back Pokédex features exactly like PLA's, but there are a few that they can take from it to improve. Bringing back the Linking Cord item that allowed players to by trade requirements for evolutions, for example, can go a long way towards helping players fill out the Pokédex more easily. Future generations can also add a few small challenges to their Pokédex entries like Legends: Arceus has to create a fun balance between the traditional version and Hisui's.
There are other ways that future Pokémon games can improve their Pokédex too. Even if they don't get rid of trade evolutions or version exclusives, they can still provide a way for players to get the missing entries for them. For example, the FireRed and LeafGreen games for the GBA let its players get the Pokédex entries for rare Pokémon that couldn't be caught wild, the Eeveelutions, from Bill since they only had one Eevee per save file to evolve into them. Something similar in future Pokémon games can make their Pokédex as good or better than Pokémon Legends: Arceus' and let players complete them by themselves.
