Pokemon GO's evolution can be as simple as using the required amount of candy, but often rarer evolutions will require an evolution item.
These are consumables that can allow you to not only fill out your Pokedex but also unlock some impressively powerful creatures.
One such item, the King's Rock, can evolve Poliwhirl into Politoed or Slowbro into Slowking, and others too, so it's worth grabbing one.
Here's how to do just that.
Pokemon GO: How To Get A King's Rock
There are a few ways to get a King's Rock, but none are guaranteed.
That means you'll want to complete as many of these tasks as possible - especially since you can only use it once.
Arguably the easiest method of earning a King's Rock, you'll want to spin Pokestops wherever possible.
Each offers a 1% chance of an evolution item, including a King's Rock.
You'll up your chances by spinning Pokestops for seven days in a row, too!
Go Battle League Reward
Speaking of PvP, try competing in the Go Battle League for a chance to earn a King's Rock as a mystery item.
For more Pokemon Go content, be sure to check out our guide to catching Magnezone.
And, with Halloween rapidly approaching, check out our Halloween guide!