As you journey through the Hisui region in Legends: Arceus, you’ll be tasked with registering the different species of Pokemon you find in your Pokedex. This Pokedex is much different from what we’ve seen in past games. With less technology available, there’s much more work involved in registering a creature's information and completing a Pokedex entry.
How to complete a Pokedex entry - Pokemon Legends: Arceus
In Pokemon Legends: Arceus, Pokedex entries are completed by fulfilling Research Tasks. Once you see a Pokemon for the first time, it will appear in your Pokedex, but it will be grayed out as it is incomplete. Going to the second page of a Pokemon’s Dex entry will show you its Research Tasks, a list of objectives that you’ll need to complete in order to finish its Pokedex Entry. Research Tasks consist of catching a Pokemon, defeating it, witnessing it using a specific move, evolving it, and many other potential assignments.
Completing Research Tasks will increase a Pokemon’s Research Level. Once it reaches Research Level 10, the Pokedex entry will be complete. You can tell a Pokedex entry is complete when the Pokemon’s portrait is colorized and there is a Pokeball icon next to its name. Once you’ve completed Research Tasks, make sure you go speak to Professor Laventon at a Base Camp in order to log your progress. If you’ve completed the necessary Research Tasks but don’t log the progress to the Professor, it won’t count.
Completing Pokedex entries is important because it not only gives you more information about a given Pokemon, but it helps you earn progress towards increasing your rank with the Galaxy Expedition Team, which yields a slew of different rewards. Now that you know how to complete a Pokedex entry, you’re ready to get out there and discover all of the creatures that Pokemon Legends: Arceus has to offer.