106.7

Some abilities produce mana based on the type of mana another permanent or permanents "could produce." The type of mana a permanent could produce at any time includes any type of mana that an ability of that permanent would produce if the ability were to resolve at that time,

Crumbling Vestige. When consider what mana that permanent "could produce", take account of not only activated ability but also triggered ability.

taking into account any applicable replacement effects in any possible order.

Fellwar Stone and Pulse of Llanowar. If your opponent controls an Island and a Pulse of LLanowar, activating Fellwar Stone's mana ability will produce one mana of any color.

Ignore whether any costs of the ability could or could not be paid.

Vivid Crag and Reflecting Pool. If you control a Vivid Crag with no counters on it, tapping a Reflecting Pool for mana will add one mana of any color.

If that permanent wouldn't produce any mana under these conditions, or no type of mana can be defined this way, there's no type of mana it could produce.

Fellwar Stone again. If your opponent controls no lands, activating Fellwar Stone's mana ability will produce no mana.

Example: Exotic Orchard has the ability "{T}: Add one mana of any color that a land an opponent controls could produce." If your opponent controls no lands, activating Exotic Orchard's mana ability will produce no mana. The same is true if you and your opponent each control no lands other than Exotic Orchards. However, if you control a Forest and an Exotic Orchard, and your opponent controls an Exotic Orchard, then each Exotic Orchard could produce {G}.

Exotic Orchard