Of course, anything made to kill another human being has an element of dubiousness about it; but some designs go above and beyond merely killing and add suffering to the equation. Here are nine of these evil weapons:
1. Boiling Oil/Hot Tar
One of the earliest forms of evil weapons. When defending a castle, use arrows and spears and rocks to simply kill. Use hot tar to terrorize and demoralize the enemy as well as kill him.
2. Mustard Gas
Mustard gas was first used in battle by the Germans in World War I with the expressed intent of demoralizing the enemy rather than kill him. The skin of victims of mustard gas blistered, their eyes became very sore and they began to vomit. Mustard gas caused internal and external bleeding and attacked the bronchial tubes, stripping off the mucous membrane. This was extremely painful. Fatally injured victims sometimes took four or five weeks to die of mustard gas exposure. (Source: Wikipedia)
3. V-1 Buzz Bomb
The V-1 rockets were not intended to hit specific targets, but instead, they were designed terrorize the population of England during World War II.
What do you do when you don't want to crawl into tunnels and pull Japanese soldiers out of their hiding places one-by-one? You strap on your flamethrower and burn them out -- a torturous way to go.
Firebombing is an air attack technique that combines blast bombing with incendiaries to yield much more destruction than blast bombs would alone. The Germans firebombed Coventry and London in 1940, and the British paid them back in spades toward the end of the war, most notably at Dresden.
6. Atomic Bomb
Since August of 1945 service academies and war colleges have studied the calculus of using the atomic bomb on Hiroshima and Nagasaki, but regardless of whether the strategy ultimately saved lives that would have been lost during a manned invasion of the Japanese homeland, it inflicted great suffering on the population in the form of destruction on an unprecedented scale and the follow-on radiation poisoning.
7. Anti-personnel Mines
These mines are designed to maim, not necessarily to kill. Stepping on them causes the mechanism to bounce up to pelvis level before exploding, causing maximum suffering before a slow painful death.
8. Punji Sticks
An evil booby trap most notoriously associated with the Vietnam War, Punji Sticks were a low-fi weapon used by the Vietcong to terrorize American forces patrolling the jungle. The sharp sticks were hidden under tarps or trap doors covered with brush, and they inflicted nasty and painful wounds to lower extremities.
A bomb full of a gelling agent and petroleum, Napalm was originally used against buildings but later became an anti-personnel weapon. The flaming goo that erupts when the weapon goes high order sticks to skin and causes severe burns.