If you own Terraria on GOG, archive the 1.4.4.9 installer immediately. You will thank yourself in two years when the modding scene moves on. If you don’t own it yet, wait for a sale, grab the DRM-free copy, and use this guide to lock in the legendary 1449 build.
On Steam, Terraria updates automatically (unless you jump through hoops with manifest IDs). If a new hotfix breaks your favorite mod or changes a mechanic you loved, you are forced to update. With the , version 1449 sits on your hard drive like a fossil in amber. It will never change unless you click "Install." terraria 1449 gog