I finally have a video for this easter egg, thanks to two wonderful fans! I had no part in its creation. Thank you, guys!

It is possible to knock Kafei over.

1. On the morning of the 1st day, leave the Clock Tower.

2. Put on the Deku Mask and lead the dog (who is trying to attack you) over to the steps up to the Laundry Pool exit, which Kafei is coming down to check his mail.

3. Position yourself so that Kafei is between the dog and you.

4. The dog will leap to attack the Deku scrub but knock down Kafei in the process, landing him flat on his face.

Oddly, Kafei’s prone form will still be moving towards the mailbox. This is because the game decrees he must still reach the postbox at a set time. This trick is likely possible because he shares Link’s model and animations. He can be hurt by the Bomb Mask for the same reasons.