The internet is full of traps. A "verified" download means the file has been scanned by VirusTotal and matches the community hash. Avoid diablo3offline.exe from pop-up ad sites.
Partially, but with major caveats. Several emulation projects have existed over the years, most notably Blizzless (formerly Blizzcon), TrinityCore’s experimental branch, and MooNet emulators. Here is the current reality: The internet is full of traps
A server emulator for a game like Diablo 3 essentially mimics the game's official servers. It allows players to experience the game as if they were connected to Blizzard's own servers, but on a privately hosted or locally run server. This can enable features such as online play over LAN or the internet without needing to connect to Blizzard's servers. In the case of an offline single-player emulator, it would allow players to enjoy the game without the need for an internet connection. Partially, but with major caveats
Go to your Diablo III installation folder. Find Diablo III Launcher.exe. Do NOT use it. Instead, create a shortcut to Diablo III.exe (the 64-bit version). Right-click the shortcut > Properties. Add this to the Target line:
-launch -offline -emu -address 127.0.0.1:1119 It allows players to experience the game as
So it looks like:
"D:\Games\Diablo III\Diablo III.exe" -launch -offline -emu -address 127.0.0.1:1119
Double-click the shortcut. The game will boot instantly without logging into Battle.net.