Final answer:
Guillaume should adopt a laissez-faire leadership style to allow his skilled and creative team of game designers the autonomy to develop the new game.
Step-by-step explanation:
Given that Guillaume has a vision for a new game development and wants to leverage the expertise and creativity of his six employees, he should consider taking a laissez-faire style of leadership. This approach allows highly skilled employees to self-manage and make their own decisions regarding the intricate interactions and details of game design. It's particularly effective when team members are skilled, motivated, and need space to exercise their creativity without being micromanaged.