Hmm Tecs:
Gas Attacks in WW1, but they hurted often the attacking as much as the defending army.
So WW1 Tecs could be: 1913 usable Tear-Gas. A Brigade, losing moral but having +1 soft core
1915 Chlor-Gas A Brigade, losing moral, but having +3 soft core
1917 "Buntschießen" A Brigade, losing moral, but having +4 soft core attack
Why moral loss? Cause the Gas often harmed the Gas-Using Divisions.
1914: Gas Masks.. increades Trickelback modifier.
1925: Decision for all Mayors: Geneva Protocol, forbidding all Chemical and Biological Weapons. ---> Deactivating all these Techs and Brigades.
generic Events: Flue and other illness especially from november till march happining 2 random divisions in your army losing some str and org over a time.
Antibiotica Techs and other medicin-Techs can stop these events. ( So these events are now more usfull )
WW2: Only the Japanese used massiv chemical and biological Weapons. Germany had very unique and lethal Gas-Weapons, but nobody told Hitler how they could attack London with a V2 and this Gas. The Amercans and Britains had plans, if Germany would use chemical Weapons in the East or against Citys in Britain, they would Bomb 30 German Citys with over 16.000 tons of deadly Gas. Over 6 till 12 Million People in Germany could have been killed, if that have happend.
So the techs for that Nations, not have signed Gneva Protocol could be:
Again attack Gas Brigades, but these Brigades will give now hugh soft attack Bonus, maybe almost 10-14 in 1943/1944.
Brigades for Strategic Bombers ( Patch 1.03 needed ), which give Bonus of 20-30 2 Strategic Bombing.
Later Chemical Weapons could be Agent Orange, giving large Bonus in the forrest and the jungle but losing morale cause of the harms for your own troops.
Finally Brigades for the Balistic and Intercontinental Rockets giving large bonus on strat. bombing.
I don't know how much the Powers had in the time of 1914-1964 biological weapons... only the Japanese tried to use them in China 1937-1945. But they could be modeled with decisions and events.
Pandemic Events like the Spanish Flue ( killed more than all causalities in WW1 from 1918-1921 ) (
http://en.wikipedia.org/wiki/1918_flu_pandemic "The pandemic lasted from January 1918 to December 1920, spreading even to the Arctic and remote Pacific islands. Between 50 and 100 million died, making it one of the deadliest natural disasters in human history. Even using the lower estimate of 50 million people, 3% of the world's population (which was 1.86 billion at the time) died of the disease. Some 500 million, or 27%, were infected " )
Nukes could be remodelled in that way, after more then one nation has the nuke ( or after 1947 ), nuklear attack should be disabled via event and only able 2 use via decision if the enemy does not accept a white peace.