Microsoft has put out a lot of big games, but none have had more riding on them than Halo 4. Microsoft Studios chief Phil Spencer said the next installment in the Master Chief series is the most expensive game the company has ever made.

Speaking to Polygon (via Joystiq), Spencer said "nothing's even close" to the amount of money the studio has dumped into the game. It's the "most important entertainment product in the company," he said, and a $3 billion franchise, encompassing other media such as comics and short films, including Forward Unto Dawn.

Developer 343 Industries also has a lot to prove after taking the reins to the series from Bungie after the first trilogy was complete. Executive producer Kiki Wolfkill said the 343's first goal was "making the game feel like Halo." Metrics firm Nielsen has already said that Halo 4 is one of the most anticipated games on Xbox 360, so fans will let Microsoft know soon enough whether it has invested its money well.