Minecraft wiki entry for Secret_door, associated text: Similar to the above, this opening mechanism uses a fishing rod and a lava pool instead of a bow and arrows. To create it, place a wooden pressure plate under a lava pool and connect it with redstone dust to a secret door. To open the door, fish onto the pressure plate and try to not look conspicuous. If the fishing bobber hits the plate, the plate should trigger the redstone, opening the door. The advantage of this over using arrows is that the door closes when you retract the bobber. Once you get good at it, the door can be opened and closed rather quickly. Additionally, other players are unlikely to waste their fishing rod's durability by fishing in lava. If someone asks why you are fishing in lava, you could use an excuse such as "I wanted to see if fishing rods burn if you fish in lava" or "I wanted to see if I could catch fish in lava" or even "I wanted to fish my pet magma cube out of the lava!" You can't fish in lava in 1.16 at least in Bedrock Edition in my experience.