Guild Wars: Bring Back The Rifts is Guild of the Week
Well worth checking out and if you haven't seen their build working on Observer Mode, keep a look out. They have a very unusual GvG build that revolves around a ton of front-loaded damage followed by minions. It's pretty hilarious to watch and typically results in a lot of explosions followed by hordes of undead minions storming into the opposing Guild Hall. I haven't seen any other GvG builds recently that managed to make good use of the Necromancer minions and the Elementalist Fire line.