There's a bunch of different pipes in Flappy Bird, each with a top-half and a bottom-half.

But we can simplify.

Thinking about it, all we need is a single top-half, which we can make appear in multiple places. We've drawn it of sufficient length that we can put it at just about any y-position, and the excess amount of pipe will just be off-screen.

For the bottom-halves, we'll just take the top half, flip it, and make it appear in multiple places.

Making the pipes appear to move is really easy -- we'll just create each top and bottom as a MySprite, and set a velocity and they'll automatically slide themselves along.

This might all sound a bit tricky, but it'll come together really well.

Watch.