BioWarfare is an up-coming mod which focuses on making warfare in Minecraft more chemical and biological. With the ability to poison enemies with nasty pathogens and turn the tide of battle, or at least turn their world upside down (Actual feature). With effects such as causing their inventory to be a mess with Diarrhea, or causing sudden death from toxins, Filling someone’s base with Bio Chemicals and Pathogens has never been so easy!
OFFICIAL SERVER:
http://www.minecraftforum.net/forums/servers/pc-servers/2506684-biowarfare-official-server
For more detailed information about the mod:
http://www.minecraftforum.net/forums/mapping-and-modding/minecraft-mods/2479828-biowarfare-bringing-minecraft-modded-war-combat-to