How do you get Sinnoh Stones?
You cannot buy a Sinnoh Stone in the shop. Here is how to get one:
- 7-day Research Breakthrough. Collect one stamp a day for seven days in a row, then you have a chance at a Sinnoh Stone as your reward.
- GO Battle League. A chance at a Sinnoh Stone as a reward after a finished set.
- PvP battles with friends. Up to three chances a day. Note that the loser seems to have a better chance of getting a Sinnoh Stone than the winner.
- Beat a Team GO Rocket leader (Cliff, Sierra, Arlo, or Giovanni). A small chance each time.
You use a Sinnoh Stone to evolve certain Pokémon, for example Electabuzz into Electivire, Roselia into Roserade, and Togetic into Togekiss.