Unless you’re a digital archaeologist trying to run a decade-old mod, there is no reason to play the Legacy version today . The Enhanced Anniversary Edition is faster, prettier, more stable, and contains 3x the content of the original. It respects the original vision while making it playable on modern hardware.
If you are playing on a Pentium 4 machine with 1GB of RAM and Windows XP, the Legacy version will run. The AE requires a DX11 GPU and at least 4GB of RAM. Titan Quest Anniversary Edition Enhanced Vs Legacy
Enhanced provides access to throwing weapons , new hero monsters, and random boss spawns that were not in the original 2006 release. Unless you’re a digital archaeologist trying to run
Note: On consoles (PS4/Xbox One/Switch), "Enhanced" usually refers to the full Anniversary Edition + all DLC. On PC, you can buy the AE and add DLC separately. If you are playing on a Pentium 4
“Legacy is the game you remember. Anniversary is the game you wish it had been.”