All the Wardens did, and the Senior Council, and several of the more responsible/combat-capable wizards who weren't either of the former (like Ebenezar, Klaus the Toymaker, and the Germans). But it wasn't literally the entire Council. Plenty of the wizards there have got precious little gift when it comes to actual combat magic–like Ancient Mai. Their strengths simply lie in other areas. Others . . . just aren't suited to it, mentally, and could probably prove to be more of a liability than an asset. Some of them are just plain chicken.
But it was a more sizeable chunk of the Council than had, at that point, ever been all together in one place to take on /one/ guy.
Guy was scary though note he also had plenty of minions and allies. Guy was one powerful fucking magic user.