Journey's End, Terraria's 1.4 update intended to be the final major content update to Terraria, launched on May 16th, 2020. 1.4 brought with it many, many new major gameplay changes to Terraria on top of a litany of bug fixes, and most Terraria fans love the update. But the Terraria community also loves mods, and modding has been a big part of Terraria for a decade. So, over a year after 1.4's release, does Terraria 1.4 support mods?
The short answer is no, but the longer answer is yes.
First, you need to understand how Terraria modding works, which is somewhat unique for a modding scene. Many games, like Bethesda games, that support mods have different options of mod loader you can use to organize your mods, but mods are mods and can be installed with any mod loader.
Terraria doesn't work like this, and it instead works a lot closer to modding on Minecraft Java. Mods are tied to a specific modding client, and over the years, different modding clients have been popular. tConfig, for example, was a popular tool for Terraria 1.1.2.
In recent years, Terraria modding has been dominated by tModLoader, a modding client that has been officially endorsed by Terraria developer Re-Logic. All mods flow through tModLoader, like Minecraft Java mods, for a long time, flowed through OptiFine.
In the Minecraft world, OptiFine updates don't usually come that quickly, leaving many with no choice but to either stay on an older version of Minecraft or live without mods until the latest version of OptiFine drops. Terraria's tModLoader situation is very similar.
tModLoader 1.4 is in active development, but it's still not out yet at the time of writing. However, you might not get that impression if you Google whether or not Terraria 1.4 supports mods, because videos and articles will come up saying there is, in fact, 1.4 mod support.
This is because in mid-2021 an alpha release for tModLoader 1.4 dropped. You can't actually find this release on familiar mod hosting sites or on the Steam Workshop, though, because it's only available through the tModLoader Discord.
It's only available there because it's an in-development, developer-only version of tModLoader not meant for casual users at all. Right now, tModLoader 1.4 is buggy and incomplete. Using it will almost inevitably break your game, because this build exists to build off of and patch.
Though, the release of the alpha is still good news. It's the first update we've got about tModLoader in a long time, and with the alpha already out, a full release is at least on the horizon. It's coming, and it's probably safe to say it isn't years out.
However, it's not all smooth sailing ahead. We don't have a release date for tModLoader 1.4, and even when it does finally arrive, mods themselves will need to be updated to support 1.4. Like in every modding community, some mods will get updated almost immediately, and others will take much, much longer. And inevitably, some mods will get lost to time.
So, it's still probably going to be a while before you can fully kit out your ideal modded Terraria 1.4 experience, even if everything goes well. But when it does come, it will be easy to use, because tModLoader is supported on the Steam Workshop.
When tModLoader is properly updated, you'll be able to access it through the Workshop as well as find and download mods with just a single click through the Workshop. This functionality will work just like how it works for the current version of tModLoader on the Workshop.
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There's also reason to believe that when tModLoader 1.4 does drop there will be a god portion of Terraria mods that get updated immediately or go live with the update, because the alpha release has been successful in allowing mod developers to work on their mods as tModLoader itself is worked on.
Back in August 2021 when the alpha just released, only a few mods (small ones, too) were updated by developers, since then, many more mods have been worked on. All of this is to say that when tModLoader drops there will likely be a good deal of mods to chosoe from and download, even if everything won't be available on day one.
It's almost important to realize that big mods, by the tModLoader team's own admission, will take a long time to update, so even if devs do have early access to tModLoader, it doesn't mean the biggest overhaul mods will make it out with the release of tModLoader 1.4.
However, if you can't wait or simply don't mind a buggy, usntable experience with limited mod support, you can download the tModLoader 1.4 alpha right now. It's only 'available' on the tModLoader Discord in the sense that the instructions for how to access the alpha are on the Discord.
You actually access the alpha as a fork of the tModLoader build available on Steam, and through Steam's 'beta build' function, you can opt to download the tModLoader 1.4 public alpha. You'll naturally need Terraria 1.4 to use this, and you'll need to find working mods to use.
Make sure to remember that even mods updated to 1.4 won't work perfectly, because the build of tModLoader being used is old, an alpha, and still actively in development. So not only are weird glitches possible, but you'll risk save data being corrupted, losing progress, and various other issues by playing the alpha at all.
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