Poison gas was the terrifying weapon of World War 1. The V1 Flying Bomb and V2 Rocket were the terrifying weapons of WW2.
There can be no doubt that the most deadliest weapon of world war 2 was the nuclear bombs that dropped on Hiroshima.
The submarine.
it was never used in world war 1
The most common one that was used as a weapon in World War 1 is called the Artillery
Man.
guns
The most common method was with artillery.It is NOT a biological weapon, it is a chemical weapon.
broken pistolthe zeppelin was the least important weapon in ww1.
the tank
Propaganda.
You can get them anywhere from Bezid.com to Ebay.com