Via the Metal Gear portal site, Konami announced the termination of online services for Metal Gear Solid V: The Phantom Pain and Metal Gear Online on PS3 and Xbox 360 starting today in phases.
“We regret to inform our users that online services for METAL GEAR SOLID V: THE PHANTOM PAIN on the PlayStation 3 and Xbox 360 will be terminated on 2022-05-31 6:00 (UTC),” says the post.
Though fans can still play online until May 31, 2022, certain online features will be removed at specific dates.
Konami shared the following schedule of events:
- 2021-08-31 6AM UTC / 2AM ET Termination of Purchase System
- 2021-11-30 6AM UTC / 2AM ET MGO related items (DLC) no longer available for purchase
- 2022-03-01 6AM UTC / 2AM ET Termination of Distribution
- 2022-05-31 6AM UTC / 2AM ET Retirement of Service
Konami reassured fans the main game will continue to be playable offline after the removal of online services. There will also not be any refunds for in-game items.
Metal Gear Online comes with two multiplayer modes. The first mode allows up to 16 players engage in online tactical warfare.
Meanwhile, the second mode allows fans to make use of the base-building feature to get items and income to use in the main single-player game.
[Source]: Konami: 2021.08.31 – [Important Notification] 【重要なお知らせ】Termination of network service (PlayStation 3, Xbox 360) – オンラインサービス終了について (PlayStation 3, Xbox 360) – [Archive].
Noticias NewsWire 
