Remakes are very much in vogue these days, providing developers the opportunity to return to an old favourite and enhance, expand, and correct the wrongs of the past. Some of the best, such as Mafia: Definitive Edition, redraw the edges of an old story, elevating and embellishing what was there in ways that seem so natural you can forget where the original began and the remake ends. With Assassin's Creed Black Flag Resynced, Ubisoft are attempting the same for their much beloved open world pirate 'em up.

Case in point, swashbuckling protagonist Edward Kenway now has nipples.

You may remember that in the 2013 original, seafaring Welshman Kenway was as blank-chested as a Ken doll. In a mark of how much technology has progressed in the 13 years since its release, Kenway now sports a fine pair of bronzed scotch pancakes. Unfortunately, I can't show you this new anatomy because the recording I came home with from a recent three-hour preview event doesn't kick in until later in my demo. However, here is an artist's rendition:

The nips aren't the only addition – it would be a bold move if they were.

Resynced is an odd collaboration of old and new. There are features from later Assassin's Creed games now worked into Black Flag's world in a way that you could easily forget they weren't there before. For instance, crouching. You can now press the [B button] to make Edward Kenway squat down and become harder to see. In the original game, you could only do that while standing in tall grass. I'm told that layered on top of that are additional stealth systems tied to the weather and time of day. Rain now dampens the sound of your movements and darkness covers the sight of them.

Other modern additions are more noticeable. Combat is now closer to Assassin's Creed Shadows, in that your enemies have a defense bar you strip away with parries, heavy attacks, and a well-timed kick to the shin. Deplete the bar and you can finish your enemy with a violent flourish. A defense bar may not sound like a leap forward - they're a feature of tonnes of games - but it is a kick in the breeches for fans of the original who enjoyed finishing their enemies after a single counter.

Another lift from more modern Assassin's Creed games is the clever way Ubisoft stuff extra moves onto your controller's standard buttons. If you hold down the right trigger your face buttons swap to a different set of moves. It's a feature that Ubisoft hit upon in 2017's Assassin's Creed Origins, and it gives you a lot more options in combat. For instance, in Resynced, hold down R2 and tap B and you'll hook a nearby enemy with a rope dart, yanking them towards you and throwing them off balance. The cost of this extra functionality is added moment-to-moment complexity. This won't be a bother to a lot of players, especially people who are up to speed with the Assassin's Creed games, but – and this may be a symptom of being dropped into a demo mid-campaign – I often felt clumsy and frustrated as I stumbled about the deck swiping ineffectually at low level enemies. The original Black Flag's simplicity made combat swift and often balletic; in my Resynced demo, I was much the drunken sailor.

There has also been a neatening of Black Flag's missions. I went back to the original game to compare their openings – which is when I spotted the nipple change, I'm not someone who just carries around a dossier of videogame chest medallions in their head – and I'd forgotten how undirected it was in the original. After surviving a shipwreck, Kenway awakes on a desert island beside a man dressed in Assassin's garb. After a brief fight, he runs off and you give chase. In the original opening, it's easy to forget your quarry and start wandering around the open island, investigating all the icons on your mini map. I was opening chests, skinning boar, and collecting Animus fragments for half an hour before I remembered I was supposed to be in hot pursuit. In Resynced, Ubisoft Singapore's stripped away those distractions to keep you focused on progressing the story. It's not a radical change, but it's an improvement and potentially a sign of a shaping that may have occurred throughout the game.

More than a neatening, Resynced also gives a much-needed scrubbing to the smudged and gloomier 2013 original. The sun seems to shine stronger, the vegetation greener, and waves bluer. I caught myself admiring the Jackdaw as the ship's keel cut through the rolling waters, its crew rushing about the deck as they did their work. Havana, too, with its terracotta slate roofs and stucco walls painted in pastel colours is a beautiful site busy with citizens to-ing and fro-ing. What I didn't see, and hoped I would, was evidence that Ubisoft Singapore had taken another note out of later Assassin's Creeds and recreated some of the less-expected historical sites – like the Lokris salt farms in Odyssey or the Hariyah dyeing factory in Mirage. Stumbling across those vividly realised locations makes those virtual worlds feel lived in in a way that the earlier games in the series could feel shallow.

Though neater in some areas, Resynced is ham-fisted in others. When you arrive in Havana, your companion's cargo is seized by a local captain. You're tasked with locating it by eavesdropping on a pair of guards in the harbour. The soldiers are so close to the mission's start, however, that as I walked up the pier, by the time the voiceover explaining my objective finished I was stood too close to the guards. They immediately spotted me, forcing them to kill them. I found the goods' location on their corpses so I could still progress, but it was another moment that left me feeling clumsy.

Sadly, it was the parkour where I felt least sure-footed. When freerunning works in an Assassin's Creed game, it's like you are wrapping the world around your feet. While holding down the A button, you pick a direction and move through the space with your character doing all the necessary scurrying, climbing, and leaping on your behalf. You can sprint up piles of crates, over rooftops, and dance across the tips of poles. Until you can't. When the game misinterprets your intentions it can send you jumping in the wrong direction, or leave you standing stock still, or most awkwardly, have you futilely scrabbling against a wall. All Assassin's Creed games have this failing to some degree, and I stumbled into it a lot in Resynced.

And, in a way that will make me sound extremely picky, when it was working I often had the sense I was being magnetically pulled from my jumping off point to my landing position, like the game had realised my leap's launch angle was off and so it would correct it for me. I realise this is a Goldilocks criticism, but I want to both have Resynced correct any faults in my movements and do it so neatly I don't notice its aid.

On the subject of sure footing, we come to the part of the preview where I worry I might be making a misstep. Calling out bugs. Whenever pointing out faults in a preview build, it has to be done with caveats. Any bugs you encounter may already be on the to-do list of pre-launch fixes. In fact, because you might be playing a build locked and polished long before the event, the bugs may already have been fixed. The process of making the preview build - in which areas of a game are lopped off and stitched together to provide a look at different sections of a much larger game - may itself be the source of any bugs you encounter. So, with those caveats in mind, here are the bugs I ran into in my preview.

The game crashed three times within the first minute of the demo's opening. I swapped machines and the game crashed a fourth time. The textures on characters' clothes popped in and out as they moved. One woman walked by with her skirttails stuck into her abdomen, revealing she was missing the top chunk of her legs. While hopping from a post to a ship in a parkour dash across a harbour, Edward slowly hovered in midair before slowly diving into the water. At one point, when I slashed the counterweight on a ship's mast to launch myself up the crow's nest, I became stuck within the mast, and had to thrash about on the controller until I got free. Finally, the capitalisation throughout the game's subtitles obey no rules of grammar.

I can believe many of these bugs will be squashed ahead of release, and across a three-hour preview session most of the game was stable. However, if they do still remain at launch, I don't want to have pasted over them at this stage. Especially because, with a remake of an already beloved game, it should arrive with a level of polish that justifies its existence.

The broad strokes of Resynced look good. Its environments are more detailed and lush, its systems more involved than the original, and its world is larger. It's a thorough modernisation of what came before. But the details are uneven. Much of the clumsiness I encountered may turn out to be a side-effect of it being a preview, ones you can blame on bugs that will be fixed and a lack of muscle memory for the skills I would have developed if playing normally, but I did feel clumsy throughout my playsession. Whether it's a true memory or age has smoothed it of rough edges, I remember the original Black Flag as a game that made me feel like a thing of controlled action. And I didn't feel that way in my time with Resynced.