The Australian federal senate is a house of review, elected from multiple member state electorates. It is usually comprised of a Government (often in minority), an Opposition (in lesser minority), and a cross-bench selection.
While the Government could obviously be overwhelmed by the opposition in the senate, the point at which Government bills required opposition support to pass, in the last period of Australian political configuration, it has generally been the cross-benches who have supplied the votes required to pass Government bills.
Given that some "cross-benches" have effectively merely been members of Government parties technically in opposition, and displayed no hostility to Government bills at all, or that Parties have sometimes governed in their own right without habitual partners:
What is the largest hostile cross-bench in an Australian house of review? In the Federal Senate? In a state house of review?