This data pack was created for Koido's Youtube channel for his request. You can see him playing above.

In this data pack, you are going to be CRUSHED by bedrock. A bedrock ceiling is created above you and a bedrock floor is created underground. The ceiling will slowly move down and the floor will slowly move up, destroying everything in their way and pushing you into the middle, until the ceiling and the floor collide – when you are between them.

When the game starts, you cannot move and can only do some configurations. The fermented spider eye in your inventory is for toggling night vision. With a bedrock ceiling above you, everything is going to be very dark and you cannot see almost anything (this also causes lot of monsters to spawn). The night vision is enabled by default, but if you want even MORE challenge you can drop the spider eye to disable it. Then you can drop the spider eye to reenable it and so on.

The book controls the display of information in the side of the screen, disabled by default. Toggle it like the spider eye. When enabled, the following information will be shown:

speed: The bedrock is moving up and down every amount of ticks that equals to this number. Configurable, default to 1200. 20 ticks are a second, 1200 ticks are a minute. Notice that the higher the number is, the slower the bedrock moves and the lower the number is the faster the bedrock moves. Don't change this to below 600.
top: The current Y position of the bedrock ceiling. Configurable before the game starts, in order to change the start height.
bottom: The current Y position of the bedrock floor. Configurable before the game starts, in order to change the start height.
timer: The timer that controls the bedrock. After you start, this increases by one each tick and when it reaches the speed (see above) it resets to 0 and the bedrock moves.
active: 1 if the timer is moving, 0 if not.
night_vision: 1 if the night vision is enabled, 0 if not.

Some more configuration (speed, top, bottom) are available using commands. Read above to see what they mean. The syntax to configure an option is:
scoreboard players set <option> bedrock <amount>Replace <option> by the name of the option you wish to configure and <amount> by the number you wish it to be. For example, this causes the bedrock to move each two minutes, instead of one:
scoreboard players set speed bedrock 2400This causes the bedrock ceiling to start on Y 150 instead of 100:
scoreboard players set top bedrock 150
After everything is configured, drop the bedrock to start and good luck! And one more thing – if you spawn on the bedrock after your death, you have failed.