Metal Gear Solid: Ground Zeroes' open world has a day and night cycle, something Hideo Kojima believes can enhance the game's replay value. The Metal Gear Solid creator told Eurogamer things like "enemy troop patterns" are noticeably different between daylight and darkness. Kojima also revealed a less inviting feature of the open world, confirming the game has loading screens.
Ground Zeroes debuted at PAX earlier this month, showcased in a trailer which saw Snake try to infiltrate a compound at night. Whether or not that particular mission is possible during daylight remains to be seen (pun intended), or what other elements are dependent on the time of day.
In the meantime, Konami has released some screenshots taken from the trailer, so you can have a hi-res gander right below.