The beat the song is built on is one bar, played through bars 6-10, 16-20 and 26-30, and 4 more places -- 61.2% of every bar the kit plays. Learn that one and the song is very nearly finished.
It is played on hi-hat, snare and kick, counted in sixteenth notes. On its own it scores 67 out of 100 -- demanding -- and the thing that decides that is the speed of the hand keeping time.
The whole song is 67 out of 100, so the beat is most of what the song asks for. Get it clean and the rest follows.
A part this hard is not learned by playing it slowly and hoping. The room opens it on its simplest reduction -- the timekeeper alone, at 78 BPM -- and adds the notes back over 4 rungs, each with a tempo to reach and a gate to pass before the next.
Tempo goes 78, 92, 106 and 120 BPM, and the gate at each one is 8 loops in a row with no wrong note and no wobble in the time.
PRACTISE THIS BEAT →A one-bar groove on hi-hat, snare and kick, in 4/4 at 120 BPM, counted in sixteenth notes. It is written out above, and it covers 61.2% of the bars the kit plays.
Bars 6-10, 16-20, 26-30 and 36-40, and 3 more places. The time is kept on the silence to start with, and it changes 3 times over the song.
67 out of 100 on its own -- demanding. The song as a whole is 67 out of 100: demanding, mostly on the independence between the hands and the feet.