Yay :D My favorite dream ever did have a Pokemon element to it.
I was playing hide and seek with an elephant/cow hybrid in a garden. It was usually easy to find because its trunk stuck out of the bushes. At one point, we were playing near a tower which supported an object that was shaped like a diamond, had a white, powdery texture and was surrounded by a black structure. I accidentally knocked it over.
Almost immediately, someone appeared before me. Apparently the object I knocked over was very important to the garden people and the elephant/cow. She summoned a black staff that's tip was a clear, see-through dome with a purple flame inside. When she summoned the staff, her entire appearance changed. She now had long purple hair, yellow eyes, and extremely pale skin with a grayish tint. She was like a human Chandelure.
The scene changed. I assume what happened between that scene and the next was that I explained that it was an accident and we became friends.
Now we were playing tag in a building which was part school, part shopping mall, part science museum. I had to hold back a lot because I was more than twice as fast as her. First we went through a classroom, then a room with a lot of glow-in-the-dark objects, then a shopping mall. To the east, the mall led to the science museum, where someone in a white lab coat was standing in front of something on display and speaking to a group of people, all of which looked fascinated.
The artifact was round and deep blue, with parts of it that were yellow. It looked like if you touched it, it would feel like a mixture of static cling and silk. I don't remember all of the explanation, but the artifact had something to do with ocean currents and lightning. It was supposedly important for understanding more about the world and helping people.