If they learn how to use the energy they have in them. It's one thing to use Chroma to buy food or to heal a wound. It's another thing to use it in converting energy something more powerful.

[ PLEASE TAKE NOTES, GOSH... It's very important to be a nerd. ]

Anytime. It's called a "Dusklight Bracelet". It's why you can see some people with animal ears or tails even when their respective moons aren't out.