Note: This article has some contents from The Legend of Spyro: Dawn of the Dragon; I did not make this up!!! I did not make any of the art shown.
The Beaver, FireClan, and WaterClan Tribes agreed to build a dam to make a border between the territories of the agreeing Tribes. After a few years since the building of the dam, Crooler's Destroyer was incinerating the land of Chima, and the dam had to be destroyed to slow the Destroyer down. Sir Fangar and the Beavers refused to let that happen, but Laval, Eris, Cragger, and Fluminox had to convince both Sir Fangar and the Beaver Tribe leader to allow the dam to be destroyed.