This. You have two of the best DR's in the game and which are two of the best for their star count (Graksmxxt and Uranus), the broken abomination that is Mokra, and a solid supporting cast that includes Murray.
Petra? Aleister? Sigma? The thing about Sak is they have solid cards at pretty much every star count.
Given that this is the Elo forum, cross out what I said about Graks and Sigma. Regardless, the core of Sakrohm is unbelievably strong. No Elo worthy card(s) in Uppers really has the impact that Mokranus do together.
Their bonus is a bit unfair, but then they have a degree of dependence on it, especially Rubie and Nellie, which makes 5/3, 6/2 or 6/1/1 splits more optimal (for me at least, had success with 6/1/1 splashing Cyb Lhia and Spiaghi).