Can and Darkness negate effect?

It seems you're asking about the interaction of "Can" and "Darkness" in the context of a game or story. However, you haven't provided enough context for me to understand what "Can" and "Darkness" refer to.

To give you a helpful answer, please tell me:

* What game or story are you referring to? Is it a specific card game, a tabletop RPG, a video game, a novel, or something else?

* What are the specific abilities or effects of "Can" and "Darkness"? Are they characters, items, spells, or something else?

Once you provide more information, I can help you figure out how "Can" and "Darkness" interact.