To receive the Endless Chainsaw, you are required to do the following:

• Defeat Adam The Clown (Wonderland Plaza)
  
• Obtain the Book Criminal Biography (Wonderland Plaza, Sir Book-a-lot)
  
• Obtain the Book Entertainment (Paradise Plaza, Bachmans Bookporium)
  
• Obtain the Book Engineering (Paradise Plaza, Bachmans Bookporium)

When you have all four items, the Chainsaw will last for it seems, forever..



If you have 3 Small Chainsaws in your inventory, it should last the entire story mode

At the start of the game, once you are on your way to help Brad, head over to Bachman's Bookporium in Paradise Plaza

First, Grab the Entertainment book:

The Entertainment book increases the durability of entertainment themed items by another 300%


After, grab the Engineering book:

Additionally, the Engineering book increases the durability of most weapons found in hardware stores by 300%, making them last three times as long as before.


After some time, head over to the Wonderland Plaza

In Wonderland Plaza, Sir book-a-lot is on the second floor. It has the book Criminal Biography -

This book increases the durability of all bladed weapons, allowing them to last three times longer than usual.


Lastly, you must fight Adam the Clown to obtain the Small Chainsaw -

Adam the clown appears in front of the Space Ride Machine, during the scoop Out of Control.


If it is your first play through of the game, Adam can seem challenging. Thankfully, all you really need to defeat Adam in this version of the game is a Handgun..

Keep a distance from Adam during the fight... Monitor him from afar... Whenever he begins to blow a balloon.. Shoot him. He will take a surprising amount of damage. Rinse + Repeat the process until he is done!


Afterwards, you'll have an endless supply of Small Chainsaws, which can last forever.

Once you have obtained all three books and the Small Chainsaw - combined - is the equivalent of Thanos with the infinite stones!

If you have any questions at all, please do leave a comment- I will get back to you ASAP

Please do vote up & favourite the guide if it was Helpful!

An alternative option for receiving an item which dose not break, and lasts forever is the Infinite Durability Book (Which was initially brought to my attention by T.Akira in the comment section below)

This book is an unlock-able object which will be granted once you obtain the Saint Achievement - the Saint Achievement is successfully obtained when you have 50 survivors SAFE and you are at the heliport for 12 on the last day.


An example above, I have 50 survivors SAFE. Now, just beat the game and the book will appear in the Security room when you start a new round!


Happy Gaming!