How to find them
Light Rocks can be found from opening mystery boxes.
How to use it
Having a Light Rock in your possession automatically attracts Thundurus in the Safari Zone, giving you a chance of encountering it while playing the mini-game. Catching it will allow you to claim a Thundurus egg into your party.
It is not guaranteed that you will encounter a Thundurus in your first try. Keep playing the mini-game until you successfully encounter and catch it.
- Light Rocks are tradeable.