The large chain of lamps are just a visual aid to demonstrate how the pulse extender works, switching off one by one as the comparators gradually lose signal strength. The only other parts of this circuit are a redstone lamp with a lever, which both allows the door to be permanently opened from the inside (and perhaps aims to teach players that lamps are solid blocks), and a pulse extender, which gives you plenty of time to make it down to the door once you activate it.

Jump up and down until you hear the pistons activate - the door will have opened, allowing you to head inside and explore the secrets the hidden room has to offer. The only accessible location not occluded with wool is directly above, so make your way up to the altar and stand against the raised section on the left-hand side as you face the portal. Because of this, making some noise to activate it is difficult, as the wool blocks the sound from almost every direction. The gimmick is simply that the Sculk is very heavily occluded with wool. It uses a Sculk Sensor (which is submerged, preventing any noise and cluing players into the existence of the secret room) to control the door - as we'll see, this is a key component for all three mechanisms. The first mechanism is arguably the simplest.

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