Just from the intro, you can pretty much tell this is going to be a Lo-fi banger by virtue of the rain samples and those deep keys.
What I loved about the drums on "Heavy Rain" is the hard hitting swing it provides. The kind of swing that'll have your head rockin back n forth from the very beginning. It's very subtle, though you'll also notice that Ellis H. has attached a slight chorus fx on the piano, making it feel so much more dreamy. When it comes to production, "Heavy Rain" is quite minimalist although by the way it slaps is certainly on maximum power.