Stupid question but what is the expected gameplay style of the Emperor’s Children?

Death Guard are slow but tanky and powerful, Thousand Sons have incredible psychic attacks to support their melee and shooting, World Eaters have the best melee and are all about rushing in and dealing as much damage as possible. So what’s the big standout method of the Emperor’s Children? From their gameplay rule it seems like speed and efficiency but that doesn’t seem too different from what I’d expect from World Eaters. Is it their shooting with Noise Marines?