From Kingdom Hearts Wiki: A world of information not accessible by Gummiship
When Riku reaches the Brink of Despair and is looking for a way into the Organization's castle, he spots Sora's Meow Wow trying to get his attention from the castle entrance. When his Komory Bat shows up as well, he realizes that they are there to help him across and uses the Dreamline to create a rope and cross the gap.
This article about an ability is a stub. You can help by .