How do you evolve Psyduck?

Question

Does Psyduck evolve by happiness, stone, item or level?

My Psyduck is a Level 27 and I want to evolve it into Golduck.

Answer 1

Which version of the game you are playing will determine what evolves psyduck. Gold/Silver/Crystal....etc.

But a waterstone or a lvl in the 30's should work.

Most versions let it evolve around the 30's.

Answer 2

Level 32 or 36.

Or a waterstone. Either one ;]

Answer 3

And why is this question is posted in Biology section?

Answer 4

www.serebii.net for all nintendo pokemon games you can use this site. psyduck evolves into golduck at lvl 33