Tell your friend to keep shaking the micro:bit to recharge the battery… Silly prank.
page 1
Page 1 shows a “battery low” animation
and waits for a shake event to switch to page 2.
page 2
Page 2 shows a “battery chargin” animation and switches back to page 1 after 5 seconds.
Since the user is supposed to keep shaking the micro:bit, it will keep returning to page 2.