"I actually tried to fight in armour myself," the game developer Daniel Vávra said. We were in the middle of a demonstration of his game in progress, Kingdom Come: Deliverance, which is nothing less than an attempt to make a no-magic, realistic answer to the epic role-playing game Skyrim -- set in a historically accurate recreation of 15th century Bohemia. Swords slide off armour or smash it, rather than effortlessly slicing through it. Stamina fades fast.