Hidden button is a meta-game , each level has completely different rules, and the rules must be inferred through observation and analysis before passing the level.
hidden button 1
（5）
In fact, it is a system of XOR equations.
（10）
（29）
（39）
（40）
Classic games from high school
（41）
The rules are similar to lighting all the lights , but with no boundaries, each cell has four neighbors according to the tire model.
（45）
（46）
This level is a hidden maze.
（48）
（49）
This is a one-stroke problem, 2 passes for the darker ones and 1 pass for the light ones. Both as a starting point and only as an end point are counted as passing.
Because it is not easy to directly judge whether it is a ring or a chain, we first analyze it by ring.
According to the strategy in one stroke , the situation of the following 8 points is easy to analyze, so a segmentation can be made and only the other points above are considered.
This graph is obtained without knowing whether it is a ring or a chain. Obviously, the result can only be a chain, so fine-tuning is required.
There are 2 light-colored points that are out of degree, so adjust the start and end points to be their neighbors.
My example is adjusted to dark dots next to them, so the resulting chain is:
Combining the upper and lower parts is the answer.
（52）
This level is actually a water pipe, but it is not convenient to watch, so I redraw it directly:
The answer is easy to find by looking at this:
（54）
This is similar to the rules of optical unlocking , the difference is that there are straight lines in it, unlike optical unlocking, which shoots directly over an unlimited distance.
So this level is quite difficult, it's always a little bit.
After many attempts, I finally found the answer:
（58）
Click the black ball to switch the maze and reach the white point.
（60）
hide button 2
（15）
This has to be drawn four times separately.
（18）
step by step to the right
（20）
Similar to Huarong Road
（40）
（41）
Three switches control three properties respectively
（45）
Similar to water sorting puzzles
（51）
（60）
