do you know what game engine the game

flappy bird uses?

thanks

Flash? I'm not sure, but the game is so basic, you could er, write it in basic. If you want to make a clone you could try Unity, or HTML5 if you're adventurous. Then again, if you're making a clone that's not very adventurous to begin with.

Not every "game" is written with a game engine. If I were to bet, I'd bet flappy bird was just coded straight-up given it's relatively simple.

Made from cardboard, popsicle sticks, and gum.