If any of you are aware of the Elevators mod for Minecraft java, I have successfully remade it in Minecraft! Now, there are some limitations as far as detection goes as I try to aim for less laggy solutions. The method I use is called "ray casting." It's kind of complicated so I'll try to simplify it. Raycasting is when you tell the game "Hey, I need you to look for something in this exact direction" and is a very common method in almost all the games you play, however, in Minecraft self raycasting is a lot slower due to performance taking the hit. (Yes, minecraft uses something similar to raycasting, ever notice how chunks disappear by the peripheral of your screen?) The raycasts I made go at a speed of 6 blocks per in-game tick (which is 1/20 of a second when no lag is introduced). I also applied a time limit, much like how the mod has a height limit. Besides that, there is one small extra feature I introduced. You can use elevator blocks 1 block away (as in 1 block away on the x or z axis respectively) and it'll still work just fine. I am quite proud of how it turned out, and I will be working on remaking other small mods in vanilla Minecraft, too!