Lego: we tested augmented reality to chase ghosts

With its Hidden Side range, Lego adds augmented reality to its constructions. That’s a pretty good point.

In recent years, Lego has built its success by opening its own stores – there are more and more in France – and by relying on flagship licenses to attract young and old (Star Wars, DC Comics, Harry Potter, Marvel…). At a time when young people are abandoning traditional toys to play Fortnite on a smartphone, the Danish company continues to offer products that combine bricks. With its Hidden Side range, which moves away from Lego’s latest successes, the multinational wants to bring a technological overlay to its know-how, which is still hitting the mark in 2019.

The different Hidden Side sets are presented as normal boxes. We start by building a vehicle or a building as if nothing had happened. Then, we download an application that transforms the construction into a video game using the magic of augmented reality. We were able to test this new 100% brand created by Lego and we can say that marriage, which is very obvious, works very well.


Hidden Side constructions are… Lego constructions like any other. So much so that some people will buy them without thinking once about augmented reality (collectors for example). The theme – ghost hunting – refers to the S.O.S. Ghosts films, which are no longer shown. The range for sale includes a laboratory, a boat, a cemetery, a truck, a restaurant, a bus, a model train and a school. This is enough to keep children busy for days at a time without having to download the application, which then acts as the icing on the cake for the most curious.

The construction itself is a form of pleasure in itself. If you haven’t assembled Lego for years, you should know that the steps are much easier to read and simpler than before (the work is a little premature). Each box contains numbered bags that correspond to a part of the set (they are referred to in the manual to avoid mixing the parts). As an added bonus, year after year, Lego invents more and more new elements so that the constructions are better finished and rich in mechanisms that allow everyone to have fun (example: projectile launchers).

The school bus provided by Lego (689 pieces for 59.99 euros) is very successful, both in terms of look (it looks like the Magic Bus of the famous cartoon) and solidity (it is heavy and imposing). The construction steps will not be a problem for regulars and there were no insurmountable tasks for the children, except for the stickers to be affixed here and there (this is not the first bus designed by Lego). The vehicle is not lacking in playability: the side doors hide weapons, the rear part is removed to access the interior and characters can easily be accommodated (there are five provided, plus a cute ghost dog).


How does virtual reality work with Lego? It’s simple. Download the right application to your powerful smartphone (at least an iPhone 7 for iOS) and embark on the adventure. It’s intuitive: we scan its construction (the bus in this case) and take advantage of interactions between the physical object and the virtual world that appears on the screen. Engineers use colors to vary the gameplay. For example, the bus is equipped with a radar that can rotate on itself and reveal different colors. You have understood the idea: this element is rotated to trigger mechanisms in the video game. This makes it possible to keep the physical object at the centre of the experiment and not make it a simple portal to the virtual world that would become useless once the application is running.

Otherwise, the gameplay consists in chasing ghosts by walking your phone around the table where the vehicle or building is placed. The technology works very well, if we respect the few criteria mentioned by Lego (flat surface and without pattern, standing rather than sitting). Once an ectoplasm is spotted, we capture it by shooting it and its projectiles that lower our battery to the game over (just tap the screen, but not too fast). The more you play, the more you progress. On this point, Lego didn’t bother: you upgrade your equipment (more power, shorter weapon overheating…), you increase the number of subscribers and the ghosts you capture gain levels (another mini-game allows you to send your army to haunt sets). Good point: there is no need to move much for magic to work, which reduces the playing area.

Hidden Side has a nice margin of progress for those who would like to dive in 100% (bosses require advanced equipment). The challenge will not seem insurmountable for the older ones, but the target audience will have something to enjoy for a few hours. Of course, you have to buy all the boxes to have access to all levels, representing an investment of several hundred euros.

Without being a showcase of augmented reality, Lego’s Hidden Side range presents itself as an interesting application of technology, coupled with a clever marriage between physical constructions and virtual interactions (as was the case with the excellent, but quickly abandoned, Lego Dimensions video game). It is simple and efficient, like a brick assembly. And we will keep in mind that augmented reality is a bonus here: Lego’s core business remains and will remain construction – another quality.