A rather large cross-forum war, where both sides constantly spam attack each other, until either:
A. A moderator blacklists everyone involved in the war.
B. One side outspeaks the other.
C. One of the forums are deleted.
The Bungie.net community witnessed a massive forum war, where the Flood forum and Zanzibar forum tirelessly spam-attacked each other, until, finally, the Zanzibar forum was deleted to make way for the Halo 3 forum.