The 3DS version of Skylanders: Spyro's Adventure uses Radiance Crystals to unlock access to higher levels. Gathering them is one of the objectives of the game, as it eventually allows access to the final level.
Earning four crystals on any level will unlock Hecktore's Challenge. Once the player completes it, a fifth crystal can be earned.
Radiance Crystals are used to fertilize crops for double the Radiance, by buying a gem-only crop type.
- According to Beaufort, a dazzling light shining from a crevasse of Rivenrock led the Seekers to a deposit of Radiance Crystals.