"OmManiPadmeOmelet" in :
> In article >,
>>
>> Chlorine gas!
>
> AKA, mustard gas I think?
> Used for chemical warfare in WW I or II?

No, "mustard" is bromobenzyl cyanide ("BBC") and much worse, I understand.
Nervous-system toxin. Both were used, and others, in the first world war.
Starting with the notorious Chlorine attack at Ypres in 1915, if I recall
right.

I had early experience with the mistake of combining household cleaners,
about age 7 (chlorinated kitchen cleanser and bleach) and saw chlorine gas
at the time and learned it was bad news.