LogFAQs > #972518765

Why would you use Dark Pulse when Crunch is the same power, runs off the higher Attack stat, and synergizes better with the other moves due to dropping the opponent's Defense

You're not gonna make anything flinch with Dark Pulse running off a 71 base Speed

Also Sandstorm is a wasted move slot since Tyranitar's ability lets it summon one upon entering battle, and Tyranitar has no other abilities that would provide an added benefit, so you're better off just using another high-power physical attack or a buff such as Dragon Dance