War-room

"In that case, I need a guide to the war-room," Edmund said, turning back to the captain.

Source: wiktionary

But instead, it was here, in the guest room cum 'war-room' of Faston and Caprice's inn.

Source: wiktionary

Abby had rigorously polished every single wooden floor with Lynton's pub machine, and they had both inspected every room and amassed a huge pile of papers, documents and old folders, from drawers, chests and desks, all carefully laid out in Uncle William's old study, becoming now the research war-room.

Source: wiktionary