Hey everyone, I just wanted to share something that I figured out. If you enter the King Louie fight with no boomerangs and no pea shooter shots left, King Louie will take an insane amount of damage from the Double Bananas.

• No Pea Shooter shots: 17 Hits
• No Pea Shooter Shots & Boomerangs: 11 Hits

I've started to change to the boomerangs at the start of Collapsing Ruins and throwing a boomerang on every jump that I make until I run out. Then I switch to the pea shooter and continue as normal.

Here's a video to show the differences and how I perform the Collapsing Ruins level: