Question

At what happiness level will Riolu evolve into Lucario in Platinum?

Answer 1

Riolu will evolve into Lucario if it has at least 220 Friendship in any game.
So if the Happiness Checker says "It's very friendly towards you. I can tell you treat it kindly." or "It simply adores you! Why, I feel like I am intruding!"
Also, every Pokémon that evolves by Friendship can evolve if it has at least 220 Friendship.

If it doesn't evolve after the Happiness Checker says "It's very friendly towards you. I can tell you treat it kindly.", then it probably isn't at 220 Happiness yet, as when they say that it could be anywhere from 200 to 254 Happiness when it's evaluated.

Hope I helped!

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Answer 2

Any Pokemon that evolves through friendship must have at least 220 friendship.
This means that you will need the Happiness Checker to say "It's very friendly toward you. I can tell you treat it kindly." or "It simply adores you! Why, I feel like I am intruding!"
Note that it cannot evolve always when the Happiness Checker says "It's very friendly toward you. I can tell you treat it kindly." because that what is said at 200-254 happiness.

Hope this helps!
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