Sounds like they struck the strings of an e-bass, then slowly turned up the volume on the amplifier. Then it sounds like just a normal/acoustic drumset kicking in...
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Sounds like distorted guitar that has a volume faded in. But also the high frequencies fade in as well. Then near the end of the fade, a crash cymbal fades in on top, it might be reversed, hard to say listening on phone speaker. Not too mention the "ughghhh".
Cymbals are reversed through most of the intro. Sounds to me like they used the low E on the rhythm guitar (single string note) tuned down to D or E flat and then used knob tuning to bring it up into the full E for that first note. Distortion on the guitar is heavy with weight in the low and mid frequencies.
It doesn't sound like a bass to me (sound would be rounder with more depth from the thicker strings) - that's the sound of a long neck guitar, possibly an Ibanez RG series. The low end on them sounds quite close to a light bass.