The best alternatives to Flappy are Dizzy Dwarves, Bolo Bird, and Chimney Post. If these 3 options don't work for you, we've listed a few more alternatives below.
What do you think of Flappy?
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The Heartstone has been stolen! You alone have what it takes to get it back! Dodge the obstacles and enemies, and avoid the DREADED POTIONS! You’ll need a combination of perfect timing, quick reflexes, memory and concentration to line up that perfect run!
Chimney post is 2D retro sidescroller game. So in this moving game, you are a post guy who is carried by a helicopter and flying over the city full of chimneys, and your objective is to hit as many chimneys as possible.