Hello! As an expert in the field of Pokémon, I can tell you that evolving Pokémon like Chansey doesn't require happiness in the traditional sense. Instead, Chansey evolves into Blissey when it is given a certain item, specifically the Oval Stone. Here's a step-by-step guide:

1. Obtain an Oval Stone: This is a special item that triggers evolution when used on a compatible Pokémon.
2. Ensure Chansey is in your party: You'll want to have Chansey in your team to use the Oval Stone on it.
3. Use the Oval Stone on Chansey: Once you have the stone and Chansey in your party, simply use the stone on Chansey to initiate the evolution process.
4. Witness the evolution: After using the Oval Stone, Chansey will evolve into Blissey.

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2 Answers. Happiness for all pokemon that evolve by means of happiness is 220. If you have a happiny, it will go from a chansey to a blissey quickly because you already had enough happiness to make it go from a happiny to a chansey.read more >>