The Oval Stone has more importance in Pokémon Legends: Arceus than other games of the Pokémon franchise. Most games in the franchise focus on the player's journey to becoming the region's champion, with the completion of the Pokédex being an afterthought. Pokémon Arceus breaks this trend, with the core gameplay loop revolving around completing various research tasks to complete the Pokédex for Professor Laventon.
Unlike most Pokémon in Pokémon Legends: Arceus, Happiny does not evolve from an increase in level or the use of a skill. Instead, Happiny is one of the few Pokémon that require using an item to evolve it. Therefore, players wishing to complete the entry for Happiny will need to evolve three of them into Chansey in order to complete the evolution task. While the entry for Happiny can be complete without this task, all three evolutions are required to get a perfect entry for Happiny.
In Pokémon Arceus, players can use an Oval Stone on a Happiny in their party to evolve the Pokémon into a Chansey. Players can do this with the Oval Stone in their Satchel while a Happiny is in their party. Then, the player can select the 'Use' option for the Oval Stone in their Satchel Menu and select the Happiny they wish to evolve. This will then take the player to the evolution animation to welcome their new Chansey into their party.
Where to Find An Oval Stone in Pokémon Legends: Arceus
Acquiring an Oval Stone in Pokémon Legends: Arceus is not a difficult feat. Players can find them lying on the ground during any space-time distortions that players encounter during their journey through the Hisui Region. In addition, the Oval Stone is a held item of Happiny. This means that the act of catching or defeating a Happiny gives players a chance to obtain Happiny's evolution stone. This means that players who find a Happiny Outbreak will benefit greatly, gaining abundant access to both the Oval Stone and the Pokémon. These options for acquiring the Oval Stone rely on luck, but there is a method for obtaining an Oval Stone that doesn't require any luck from players.
Pokémon Legends: Arceus lets players spend Merit Points to acquire evolution stones like the Oval Stone if players have been unlucky in their attempts to obtain it. Most evolution stones cost between 1000 and 1400 Merit Points to purchase. The Oval Stone is much cheaper than all of the others, selling for only 400 Merit Points. Merit Points can be spent by talking to Simona, located just east of the Training Grounds in Jubilife Village. Players in desperate need of an Oval Stone will find no better method of acquiring one due to how cheap the Oval Stone is to purchase from Simona. With their new Oval Stone in hand, players will be one step closer to completing the Pokédex in Pokémon Legends: Arceus.
Pokémon Legends: Arceus is available now on Nintendo Switch.