Knot-Wing the Koopa's Fort

Knot Wing the Koopa's Fort is the thirteenth level of Yoshi's Woolly World. It contains the game's third boss, Knot-Wing the Koopa.

Layout
The level mainly focuses on using Keys to progress.

After finishing the level, Kamek will enlarge Knot-Wing the Koopa, engaging the boss battle. To defeat Knot-Wing, Yoshi has to eat his wings, and then ground pound his belly. Knot-Wing will then retreat into his shell and charge at Yoshi while ricocheting off walls. Knot-Wing is defeated after the third hit.

Enemies

 * Koopa Troopas
 * Shy Guys
 * Piranha Plants

Smiley Flowers

 * Smiley Flower 1: On the left side of the starting point, guarded by three Piranha Plants. To get at it, Yoshi must eat a Koopa Troopa and spit out its shell at the Piranha Plants, defeating them all.
 * Smiley Flower 2: Inside a hidden Winged Cloud, almost immediately after the door concealing the second Wonder Wool.
 * Smiley Flower 3: In an alcove immediately below the first checkpoint. Yoshi must ground pound the blocks and step through the one-way gate to the Smiley Flower.

Wonder Wools

 * Wonder Wool 1: At the alcove above the left green warp pipe near the start of the level. To obtain it, Yoshi must eat the wall on the left.
 * Wonder Wool 2: At the very top of the first section of the level, a hidden Winged Cloud is present. Yoshi must throw a yarn ball at it to reveal a door. Inside that door, Yoshi must then use the nearby Koopa Troopa to defeat all of the Hook Guys and obtain the Wonder Wool.