Flappy Jetplane
You operate a small flying ship with hyper-nano-quantum engine that flies through the tunnel deeply under the ground in desperate attempt to reach the end.
Unfortunately hyper-nano-quantum engine allow you to change only vertical component of speed, it means that you can only fly up or fall down.
Flap your “Jetplane” to fly up, do nothing to fly down.
Please note that collisions with any obstacles or walls explode the ship!