Flap through the sky and dodge the towers. Every 10 seconds, you must answer a science question to keep flying.
Correct answer: keep flying for 10 more seconds.
Wrong answer: you get shot out of the sky.
Hit an obstacle: game over.
Survive longer: obstacles get faster, gaps get tighter, and towers appear more often.
Controls: Spacebar, mouse click, tap, or ↑ arrow to flap.