In Minecraft, to activate a conduit we need the conduit itself, which can be crafted using 8 nautilus shells and 1 heart of the sea. We also need 16 to 42 blocks of Prismarina, which can be found in marine temples. If you use 16 blocks the range will be 31 blocks, if you use 42 blocks the range will be 96 blocks.
You will have to activate it under water. Nautilus shells can be found by killing drowned men holding one in their hand, or by fishing in the sea. The heart of the sea can be found in shipwrecks or as loot from treasure maps.
For 16 blocks you will have a range of 31 blocks.
It offers too little range, so it is much more convenient to use the second or third methods, which offer a better range. For 30 blocks you will have a range of 63 blocks. For 42 blocks and you will have a range of 96 blocks.
With the Heart of the Sea item in particular, it can be used to create a special Underwater Conduit which will not only allow players to see better, but will also prevent breath from diminishing, allow for underwater night vision, and increase draw speed.
Magnetite is a block that can be used to change the direction in which a compass points. It can be used in all 3 sizes. By combining a Nether Wart together with a Water Bottle, you will make a Strange Potion. This potion is the basis for obtaining an Aquatic Breathing Potion.
Therefore, leaving the Weird Position inside the Still, use the top slot of the Still to add a Puffer Fish as a reagent. The Ancient Guardian will swim around a bit before firing again. If the target approaches the Ancient Guardian while he is firing his beam, he will stop firing and swim away until he is at a suitable distance, where the attack will resume.
To activate a conduit we need, of course, the conduit itself, which can be crafted using 8 nautilus shells and 1 heart of the sea. Nautilus shells can be found by killing drowned men holding one in their hand, or by fishing in the sea.