A war that consists of a series of attacks between 2 or more groups. In a rank war any weapon is acceptable, though the most popular weapon of choice are Rank Bombs, filled with fermented unrecognizable items/liquids. Only a few rank wars has happened, for a good reason.
Todd: oh god, did he just start a rank war
Zoe: he freaking did, what do we do?
Dave: RUN GODDAMN IT WHO KNOW WHAT COULD HAPPEN!