Do you have to complete all Dex entries to get Arceus?
Pokemon Legends: Arceus does require players to complete the Pokedex in order to face Arceus, the game's namesake, but it's well worth it. Players who want to add Arceus to their party have no way around completing the Pokedex.
Beating Darkrai in Pokémon Legends: Arceus
Fortunately, since capturing Darkrai is required to complete the Request, the Mythical Pokémon will respawn after trainers return to Jubilife Village if they accidentally knock it out in battle.
Completing All Research Tasks. When a player has completed enough Research Tasks, their Research Level will continue to climb. At 10, they'll be able to view their entry. Completing all Pokemon's entries in the Pokedex is the only way to get the Shiny Charm in Pokemon Legends: Arceus.
Darkrai and Shaymin require a different game to get, so they definitely aren't needed to get Arceus.
As you may have guessed from the not-subtle hint, you'll need to capture all the remaining Pokemon before the Azure Flute will summon Arceus. That will mean capturing almost every Pokemon in the game, which is no simple task. You'll need 237 Pokemon in all, and it will be the first 237 in the Pokedex.
Players will need to find 107 Spiritomb Wisps around the Hisui Region in Pokémon Legends: Arceus in order to complete a request and catch Spiritomb.
It's just that completing every quest, including the 94 requests, won't acknowledge the player's work. Pokemon Legends: Arceus does offer a reward for completing the game's Pokedex and capturing all in-game Pokemon. Players get a Shiny Charm, which should improve their chances of acquiring shiny Pokemon.
Example of Research Level calculation
Keep in mind that even if your points would go over 10, your Research Level will max out at level 10 and stop increasing.
The Shiny Charm will increase your chances of finding shiny Pokémon in Pokémon Legends: Arceus and, to get it, you need to reach Research Level 10 for every Pokémon in the Hisui Pokédex.
Unfortunately, the only official way to get the Member's Card is by attending a Nintendo event which ended in 2009. You can still get Darkrai, but you will need to perform void glitch that gets you to an darkrai encounter, or use an Action Replay to hack the game.
Can you get Darkrai without member card?
To encounter Darkrai, you'll need to have the Member Card, which will be distributed via Mystery Gift between April 1 and April 30. Once you've obtained the Member Card, you'll gain access to the locked inn at Canalave City. Upon entering the inn, you'll travel to Newmoon Island, where you'll encounter Darkrai.
Darkrai. If you have play records from the Pokémon Brilliant Diamond or Pokémon Shining Pearl games, you'll be able to take on a research request in Pokémon Legends: Arceus in which you'll have a chance to add the Mythical Pokémon Darkrai to your team.
It's weak against Bug, Fairy, and Fighting-type moves, so try to get it as low as possible before using some of your best balls to catch it. Don't worry if you knock it out by accident - you can leave the Coronet Highlands then return to the same spot and Darkrai will respawn.
What that means, if you don't know, is that you first need to catch every other Pokémon in Pokémon Legends: Arceus, including ultra powerful ones like Palika, Dialga, Regigigas, and more. The only ones that don't count are the Mythical Darkrai and Shaymin. This will total 242 Pokémon you need to add to your collection.
How long does it take to finish Pokémon Legends: Arceus? Pokémon Legends: Arceus takes between 20 and 30 hours to complete if you're solely focusing on the main story.
When focusing on the main objectives, Pokémon Legends: Arceus is about 25 Hours in length. If you're a gamer that strives to see all aspects of the game, you are likely to spend around 78 Hours to obtain 100% completion.
If you couldn't enjoy your first fight with Dialga, Palkia, or Arceus during your first encounter with them, you can try again later in the game.
How to unlock more requests. Most requests open up as you complete the main story in Pokémon Legends: Arceus, and they're indicated by a dark blue quest marker with a white circle inside. The further you get in the story, the more requests will unlock.
The fastest way to progress with the research tasks is to catch or defeat Pokemon. Catching Pokemon can efficiently raise the research level of almost all Pokemon, so we recommend bringing out your Pokeballs first to try your luck at catching them before attempting to defeat them in battle.