"Hercules, Samson, and Ulysses" (Italian 1965)
In this catagory, nothing can touch it. This is the alltime worst movie EVER made that is SO BAD, you will be rolling on the floor begging for the TV to be turned off.
The plotline is ridiculous. The three famous super legends team up to fight the evil Philistines who just happen to be wearing Nazi helmuts. (Yes, they are that evil!)
There are dozens of absolutely stupid lines. Like when the Philistines were looking for Samson in a village, the commander tells his troops, "Be sure and look for dead lions in the rooms, he is known to kill them" Or Ulysses yelling out to Samson, "Watch out for Delilah, I don't trust that women!"
This is also a winner of worst special effects in a movie for the use of foam boulders. The fight scene between Samson and Hercules is classic. Sound effects when spears are thrown are as incredibl as how they magically somehow appear in warriors hands.
This film can be found in the TCM library of Movie Classics.