the something to end all sths
the/a (something) to end all (somethings)
That which outclasses or is more impressive than anything else of its kind could ever hope to be. Many people still believe that, from a technical filmmaking perspective, Citizen Kane is the film to end all films. I remember when we all thought this impressive machine was the computer to end all computers. Now it seems positively archaic compared to the devices we all use today.