Assassin's Creed III Remastered Ultrawide Fix: 21:9, 32:9, and Hex Options

Why the Assassin's Creed III Remastered Ultrawide Fix Is a Community Project

If you launch Assassin's Creed III Remastered on a 21:9 or 32:9 panel and the image stretches, the HUD drifts off-center, or cutscenes snap back to a boxy 16:9 frame, you are not imagining things. Players have been chasing a clean Assassin's Creed III Remastered ultrawide fix since the remaster's early days, and the most detailed public record of that effort is a Widescreen Gaming Forum (WSGF) thread whose posts date from late March and early April 2019.

That matters because there is no single official toggle to point you toward in that record. Instead, the Assassin's Creed III Remastered ultrawide fix exists as three community approaches, each with a different trade-off: a Flawless Widescreen plugin, a Cheat Engine aspect-ratio table, and direct hex editing of the game executable.

This guide summarizes what those players reported, in their own words and with their own dates, so you can pick the method that matches your risk tolerance. Everything below is player experience from 2019, not an official Ubisoft or Steam statement, and results can vary by store version, GPU, driver, and patch level.

What the WSGF Thread Actually Reported

The thread, titled "Assassins Creed III Remastered need a Ultra Wide Fix," is a running conversation rather than a polished tutorial. That is exactly why it is useful: you can see which fixes held up and which fell apart for other people.

Two things stand out. First, every working Assassin's Creed III Remastered ultrawide fix in that thread is a third-party tool. Second, no single method solved everything — hex editing got the widest coverage but wrecked the interface, while the Flawless Widescreen route kept the HUD intact but left cutscenes pillarboxed.

Option 1: The Flawless Widescreen Plugin Route

This is the method most people try first, because it is reversible and does not touch your game files permanently. Wintermance described it as a "cobbled together fix" built on the existing Assassin's Creed IV plugin, posted on 30 March 2019.

The steps, as described in the thread:

1. Install Flawless Widescreen on your PC.
2. Download the community UWFix.zip attached to the WSGF thread.
3. Copy its contents into your Flawless Widescreen installation directory.
4. Launch Assassin's Creed III Remastered, then choose the 21:9 aspect ratio inside the Flawless Widescreen interface.
5. If nothing changes, switch the in-game aspect ratio back to 16:9 and then to 21:9 — the poster said this "kick in" trick was needed in some sessions.

The honest limitations: Wintermance noted the fix "seems to work well in gameplay but the ingame cutscenes are still locked to 16:9." Later in the same thread, a user named valcan_s reported that the plugin did not detect the process at all on a 5760x1080 Nvidia Surround setup, and said their copy was a legitimate Uplay version. Wintermance replied that all of their own testing had been done on the Uplay version too, so store version alone does not explain the failure.

If you try this Assassin's Creed III Remastered ultrawide fix, back up your Flawless Widescreen folder first so you can roll back cleanly.

Option 2: The Cheat Engine Aspect-Ratio Table

When the plugin route failed for valcan_s, Wintermance offered a second path on 1 April 2019: a Cheat Engine table containing what they described as the correct addresses for the aspect ratio, plus the arithmetic behind the values.

The formula is simple and worth writing down:

• AspectRatioVH = Height ÷ Width
• AspectRatioHV = Width ÷ Height

The two worked examples from the thread:

Wintermance said they had personally verified other ratios, including 32:9, using the table and those calculations — a useful data point if you are running a super-ultrawide display. They also repeated the same workaround: if the values won't take at startup, flip the in-game video settings from 16:9 to 21:9 so the new numbers apply.

Compared with hex editing, this Assassin's Creed III Remastered ultrawide fix is far easier to undo — close Cheat Engine and you are back to stock behavior. The catch is that it only affects the running process, so you will need to reapply it each session, and address tables can go stale after game updates.

Option 3: Hex Editing (Highest Coverage, Highest Cost)

Seaclean reported on 29 March 2019 that they had edited hex values and managed to get both cutscenes and gameplay running in 21:9 — but that "the HUD is messed up." A follow-up post on 30 March laid out the procedure using the HxD hex editor, with ResHex offered as an optional helper.

The published search-and-replace values:

The workflow is to open the executable in HxD, search for the hex sequence 39 8E E3 3F in "Hex values" mode with search direction set to "All," and replace every instance with the value for your resolution.

One important caution: the poster's step-by-step text names ACOdyssey.exe as the file to open, which looks like it was carried over from an Assassin's Creed Odyssey ultrawide guide rather than written specifically for the remaster. Verify which executable you are actually editing before you save. Keep a backup of the original file, expect a stretched menu and HUD, and treat this as the last resort among the three — it is the only method here that permanently modifies game files until you restore your backup.

Troubleshooting Checklist Before You Give Up

If the Assassin's Creed III Remastered ultrawide fix appears to do nothing, work through the same checks the WSGF posters used:

• Confirm injection. On Flawless Widescreen, check the readout area for process-attach messages. valcan_s used exactly this observation to conclude the plugin was not latching onto the game.
• Toggle the aspect ratio. Multiple posters found that switching 16:9 → 21:9 in the video settings forced the new values to apply.
• Match the tool to the store version. The thread's original testing was on Uplay copies; Steam users may see different process names or behavior.
• Separate gameplay from cutscenes. Cutscenes remaining 16:9 is a known limitation of the plugin route, not necessarily a broken install.
• Test a second resolution. If 21:9 fails, the Cheat Engine table lets you try another ratio like 32:9 with a quick recalculation.

For reference on the game itself — supported resolutions, system requirements, and patch history — see Assassin's Creed III Remastered on Steam. For the full conversation, including the attached files and screenshots, read the WSGF ultrawide thread for Assassin's Creed III Remastered.

FAQ

Is there an official Assassin's Creed III Remastered ultrawide fix from Ubisoft? Nothing in the WSGF thread from 2019 points to an official ultrawide mode, and the players there built their own workarounds. A player also reported that Liberation's in-game aspect ratio setting offered only 16:9 even at 2560x1080. Check the Steam page and current patch notes before assuming nothing has changed.

Which Assassin's Creed III Remastered ultrawide fix is safest? The Cheat Engine table is the easiest to undo, since closing the tool restores stock behavior. The Flawless Widescreen plugin is second, provided you back up its folder. Hex editing is the riskiest because it alters game files.

Why are my cutscenes still in 16:9 after the fix? That is the documented behavior of the Flawless Widescreen plugin route from 30 March 2019 — gameplay widened, cutscenes stayed locked. Only the hex-edit approach was reported to widen cutscenes, at the cost of a stretched HUD.

Will this Assassin's Creed III Remastered ultrawide fix work at 32:9 or triple-monitor resolutions? Mixed reports. Wintermance said 32:9 worked through the Cheat Engine table, but valcan_s could not get the plugin to attach at 5760x1080 in Nvidia Surround. Try the table first for super-wide setups.