will be defending something, and 
will destroy it! unlike demolition the defenders ( ) will respawn infinitly and the attackers ( ) will have a limited amount of reinforcements (respawning) before the game is over! and the best of all for those people who like destroying stuff, the blocks are fully destructible!(IF you dont know what gold rush is. then click this link)
https://www.youtube.com/watch?v=MSkmXRexf2o
This game mode will be on various maps like these (and many more too)