You will get TM10 Hidden Power from Professor Juniper as a reward after you’ve seen at least 120 different Pokémon in the Unova region. Note that you just need to see 120 Pokémon in battle, so you don’t need to catch or evolve 120 species.
The Professor’s location varies depending on where you are in your journey, but she can usually be found at her lab in Nuvema Town.
As for the move details: Hidden Power is technically a Normal-type move, but its typing actually varies based on the user Pokémon’s Individual Values (IVs.) The attack’s Power is also dependent upon IVs, and can range anywhere from 30-70.
Tip: If you’re interested in learning what type Hidden Power would be on any of your Pokémon, there’s a Hidden Power checker NPC located in the Mistralton City Pokémon Center.
TM10 Hidden Power Location (Step-by-Step)
Step 1: Starting at your home in Nuvema town, head northwest on the dirt path.
Step 2: To the north is Professor Juniper’s lab (with the red roof). Enter the lab.
Step 3: Speak to Professor Juniper, who should be standing in the center of the lab.
Step 4: After showing the Professor your Pokédex with 120 different Unova Pokémon (seen, not caught), she’ll give you TM10 Hidden Power.
Checking Your Hidden Power Type
To check your Pokémon’s potential Hidden Power type, make your way to Mistralton City.
There’s a Hidden Power Checker NPC inside of Mistralton’s Pokémon Center wearing a green shirt. He can identify the Hidden Power move type for any Pokémon in your party.
Hidden Power Details + Uses
|Hidden Power Move Details|
Hidden Power is one of the most unique attacks in Black/White, because its Power and typing is completely dependent upon a Pokémon’s IVs.
The move’s Power can range anywhere from 30 to 70, with the potential to be a solid attack for a Pokémon with high IVs.
Move types like Fire, Ground, and Ice are most-sought after, since they provide the best type effectiveness coverage.
It also helps for your Pokémon to have a Hidden Power that is super effective versus the type they’re weak to.
For example: a Water-type Pokémon with a Fire-type Hidden Power can catch a Grass-type enemy by surprise.