Platforms
Asus ROG Ally
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The Asus Ally is a handheld gaming device and Steam Deck competitor. Diablo 4 should run great on it.
Linux version?
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Players on Linux distros won't have native support for Diablo 4, but can use Wine and Lutris to play.
Mac version?
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There will be no native Mac/MacOS version of Diablo 4. Players will likely be able to use Boot Camp to play.
Mobile version?
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Blizzard won't be releasing any version of Diablo 4 on mobile devices. Diablo: Immortal will have to suffice.
PC controllers
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For the first time in a Diablo game, PC players can use controllers, just like console players can.
PC Requirements
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You'll need a somewhat modern machine and to handle Diablo 4's demanding gameplay.
Platforms list
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The game has three official platforms for its June 6, 2023 release date: PC/Windows, PlayStation, and Xbox.
Steam Deck
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Valve's popular handheld gaming device, the Steam Deck, should support Diablo 4 -- with tweaks.
Switch version?
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Unlike Diablo 3, there will be no Nintendo Switch version of Diablo 4. The hardware demands are too high.
Settings
Error codes
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Diablo 4 has over 150 error codes to help players understand login, messaging, and multiplayer issues.
Gameplay settings
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Health bars, highlights, item labels, tooltips, and more are customizable in Diablo 4's Gameplay Settings.
Graphics settings
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Diablo 4 will support a wide range of screen resolutions, aspect ratios, and devices, including ultrawide monitors.
Keybinds
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There's keybinds for skills, movement, potions, mounts, and more in the Settings > Controls tab.
Languages
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Similar to other Blizzard titles, Diablo 4 will likely support many of the top spoken languages in the world.
Social settings
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Chat windows, chat bubbles, and notifications can all be tweaked to the player's liking in Diablo 4.
Sound settings
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Players can adjust volume controls, voice chat, text-to-speech, subtitle, and loot drop sounds.
Misc
Addons?
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Blizzard won't allow addons in Diablo 4, but is integegrating many quality-of-life features into the game.
Offline mode?
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Players will always have to be connected to the Internet (and Battle.net) to play Diablo 4.
Impressive graphics, flexible settings
Diablo 4 will be the first in the Diablo series to allow cross-play between PCs and consoles (Xbox confirmed, with PlayStation likely). Also, for the first time, PC players can use controllers if they wish. Blizzard has no plans to support third-party addons, hoping to implement everything players need in-game, or an offline mode, since the connected and multiplayer aspects of the game offer the best experience.