Based on how it's worded, the effect doesn't care where the spell was cast from. Whether it's from your hand, exile (as is the case with madness) or library. The wording would be more specific (Examples: Reiver Demon, Melek, Izzet Paragon).
Cascade goes by the card's CMC, not alternate costs used to pay it, such as madness or evoke. Evoking Mulldrifter for 2U will allow you to cascade for a card with CMC<5.
I don't like them. This is the kind of card I see punishing the new guy that's using guildgates over the 9-fetches guy. Sometimes you take people by surprise and land it while they have a bunch of nonbasics, but more often I see this punishing the budget players with their etbt duals.
I fail to see how it affects them differently. It punishes them both equally. Gates and fetches are both nonbasic and thus become Mountains under the Blood Moon.
Deadeye Navigator is the card you're looking for.
Based on how it's worded, the effect doesn't care where the spell was cast from. Whether it's from your hand, exile (as is the case with madness) or library. The wording would be more specific (Examples: Reiver Demon, Melek, Izzet Paragon).
I fail to see how it affects them differently. It punishes them both equally. Gates and fetches are both nonbasic and thus become Mountains under the Blood Moon.