With their attacker hidden, Link doesn't have a clear shot either. He can't directly shoot an enemy he can't see.

Luckily for Link and Donnie though, he doesn't have to.

Because to his arrow he fuses a mushroom that will be quite familiar to Donnie - a Puffshroom. As it lands, it explodes into a cloud of fog-like spores - and utterly obscuring the area.

Which means that right now, their enemy can't see anything - and Link takes this opportunity to move, heading right towards the Puffshroom cloud.