Happy New Year everyone!

It's been awhile, but we're finally ready to release this massive devlog we've been hyping up for months. We hope everyone has a great 2025!

We've recently released the Undertale Plus Reveal Trailer in UnderEvent 2024!

This trailer has been in the works since late May of 2024. We're all really happy that we finally get to talk about it!

If you missed it, you can watch the official trailer here:

So, let's talk a little bit about the trailer!

Our New Mascot!

Undertale Plus was in a very special position going into UnderEvent. Since we're just modifying the original Undertale, we don't have many original characters. We needed one for UnderEvent, so one of our Directors, Nelle, made this Frisk!

We believe it fits into our creative vision for the project. You'll be seeing them across our future promotional material!

Alrighty, I'm sure this is what the majority of you all are interested in. Undertale Connect+

We are adding full online multiplayer support in Undertale Plus. You can play through the entire Undertale story with your friends!

I'm sure some questions will be brought up, so let's go over a few!

• Is Connect+ a separate mod?

  No. Undertale Connect+ will be included in a future update after the release of Undertale Plus. It will be a new toggleable Addon that will be packaged in the main download.

• Is everything going to be synced?

  It's toggleable! You have the option to either sync everyone's save data and game or isolate and see others as live player ghosts! We wanted to encourage casual play among friends, as well as encourage speedrunning races!

• Do I need to port forward or set up a server to play?

  These are both valid options to host on Connect+, but there is a way to host Connect+ sessions without port forwarding and setting up a server with software such as Hamachi!

• Can we stack all content in Undertale Plus on Connect+?

  Yes, with a few limitations. We're attempting to make as many Addons work with Connect+ as possible, but there will be a few that unfortunately won't be compatible with Connect+. We will announce those Addons at a later date.

• Is Connect+ permanently on?

  No. Connect+ is toggleable like every Addon and setting in Undertale Plus.

Let's talk about what Connect+ has to offer! Please keep in mind that everything talked about here is not final and is subject to change in the future. In addition, we will not reveal everything about Connect+ in this devlog.

Custom Skins

This menu is still a work in progress.

Connect+ will be able to support custom skins! The GIF above showcases the skin librarby.

Just like Minecraft, you can create your own skins. When Connect+ releases, we will release a basic template for creating your custom skins! The goal is to make a place on our Discord to upload the skins to for people to download.

When you add a new custom skin, the game will automatically detect that skin and place it in this list! It also comes with a search bar so you can find them easily.

See everyone's SOUL in battle!

When in battle, you'll be able to see everyone's SOUL!

Landimizer is currently leading development on Connect+. Building off of both his mod (download here) and LuigiUTMC's Undertale multiplayer prototype!

The Deltabattles Addon was also showcased in the trailer! It mainly went over some fights, but there's still some stuff we can talk about.

Please keep in mind, that Deltabattles is still in it's infancy and most of the Deltabattle content shown in the trailer is not finished. This probably sounds disappointing to some, but we are working really hard behind the scenes to bring this project to you. Deltabattles is one of the hardest things on this project to develop. So we hope you understand.

Here is our rough draft of Toriel's fight. Her sprites are likely going to be redone, but I think this gives everyone a good idea on how we want the final version of Deltabattles to look. If you notice, Frisk is holding a stick!!!!!!! This is one of the weapon/armor sprites we currently have implemented into the game!

The font used to display the fallen human's name in Deltabattles is a custom font created by Nelle Fox!

Here's a closer look at the Mettaton EX fight in Deltabattles!

I think this gives a better idea on how settings and Addons can be stacked on top of each other. For example, Undertale Yellow's Wild Revolver is an available setting, and if you enable Deltabattles at the same time; you get the benefit of the Wild Revolver! Please note that this is not a confirmation that each weapon will have custom ways of attacking.

For reference, the Wild Revolver goes over the Empty Gun and the Cowboy Hat is also an armor you can equip that already exists in Undertale.

Here's a video showcasing the Muffet fight that was in the trailer. We originally were going to do her attack where she calls her pet, but once our trailer got extended past 30 seconds, a different attack was chosen because it looked better in 3D.

Still, the efforts to restore that attack still took place and so I wanted to bring forward this video.

Please note that this was recorded back in October of 2024. There aren't any sound effects in this video because it was recorded for trailer purposes. In addition, THIS GAMEPLAY IS NOT FINAL. There's a lot of things visually in this fight that don't look good and the fight at the moment is still not able to be completed.

I hope you all enjoyed UnderEvent as much as we did! Next month there will be another devlog, so to stay updated, please join our Discord Server for frequent previews and discussions around our project!

Thank you everyone at UnderEvent for giving us this opportunity! It was a pleasure collaborating with you all!

Update On Decomp Port

Currently, the majority of Undertale Plus has been ported from Linux v1.001 to Undertale Decomp. We even have fixed inputs ported and working to a degree. The only big thing left, outside of a few bugs, is Widescreen support. This is mainly because we're currently discussing different ways of how Widescreen can function and we haven't settled on any concrete answers yet.

If you don't know what I'm talking about, please refer to last month's devlog.

Oh yeah, remember back in September 2024 when we did our second devlog? We mentioned a reoccurring bug where players would get stuck in the rock in Ruins if you talked to it from behind.

Well...

Guess...

W H A T?

IT HAPPENED AGAIN!!!!!

Porting to Undertale Decomp brought the rock bug back from the dead.... again....

We'll be sure that this rock is in working order for the full release.

In the meantime, check out our website - https://www.undertaleplus.com