Art Of War mod is partial-conversion modification adding lots of new features to old Zero Hour's gameplay, they are discussed in summary.
Replaces Rocket Buggy. The Nebelwerfer is old German chemical rocket mortar from times of WW2 (the key worg here is "chemical"). It launches up to 12 unguided missiles with toxins. Gains 6 more launchtubes when reaches third veterancy level.