War in Blobiverse is completely out of your control. After a certain point in the game, two Blob Factions(colors) can go to war. It start with a blob announcing the decision of war. Then the faction gets a small army (2-4 blobs with weaponry) and attack the faction they chose to fight. This goes on for a while until either faction loses all population. Nothing happens after that. All that's left of the defeated blobs is an empty town, which is a bit lame. To know if a faction wants to start a war, wait for some blobs to talk about another faction. The color of faction will be shown with a few symbols, each meaning their own thing. A sword means they want war. Two swords also means that they want war. A chest means they want to trade and have relations. There are many more, but one stand out. A skull means that they want to destroy and kill all of a faction. This symbol is mostly used during wars, or after. That's about it for war.