Lego's brick-built Game Boy replica is bound to be one of the most popular gift ideas for retro gaming enthusiasts this holiday. The 421-piece recreation of Nintendo's legendary 1989 handheld is wonderfully designed, fun to build, and looks great on a display shelf. It comes with two buildable games, The Legend of Zelda: Link's Awakening and Super Mario Land, which can be loaded into the handheld's Game Pak slot. Swappable lenticular screens recreate moments from each game as well as the Game Boy's boot screen. The $60 price tag makes it one of the most affordable Lego sets made for adults. The Lego Game Boy launched October 1 at the Lego Store and major retailers, including Amazon, Walmart, and Target.I spoke with Lego Group Senior Designer Carl Merriam over email about the design of the newest Lego Nintendo display model. Questions and answers are attributed to GameSpot and Lego, respectively.GameSpot: I've always been fascinated by the logistics of designing a LEGO set. How do you start? How do designers determine how many pieces each build should have? How do you choose the shapes and sizes of the pieces? Did the Game Boy go through multiple iterations before finding the right design? Can you provide a general overview of how a designer gets from the idea to a finished product?LEGO: We start with an idea. For the LEGO Game Boy the idea was: “Let’s make a LEGO set celebrating the original Nintendo Game Boy.” From there we built several different versions using existing LEGO Bricks. While doing that we determined that we would need a few new LEGO elements. We started developing the new LEGO elements and built many, many, many more versions of the LEGO Game Boy. Eventually we found combinations of pieces that looked like the reference, are stable when built and most importantly are fun to put together.Lego Game Boy 72046GameSpot: Does the LEGO Game Boy set use any unique pieces not found in other LEGO sets?LEGO: We developed a special 4x4 curved LEGO brick for the corner with the speaker, as well as a 6x8 tile for the back plate and a 2x4 bracket to build in the buttons. Many of the other pieces were existing bricks. The start and select buttons are tires, which originally launched in 1969, the A and B buttons are minifigure hats, AND we even managed to include a classic 2x4 brick inside.GameSpot: What did Nintendo bring to this design, in terms of knowledge, advice, and secrets?LEGO: We work closely with Nintendo on all LEGO Nintendo products, and the Game Boy was no different. One of the most fun parts was working with Nintendo on what easter eggs to include and what game screens to replicate from Super Mario Land and The Legend of Zelda: Links Awakening. Nintendo provided both design input on the build, as well as reference images of the actual hardware components.GameSpot: How important was it to make this set not only look like the Game Boy, but also feel like an accurate replica of a handheld device? At the same time, aspects such as visible studs on the D-pad make it evident this is a LEGO set. I imagine it's critical for a replica to still look like a LEGO set?LEGO: During the development of this set, we built many versions with different levels of functionality. Given the size of the original Game Boy, we were presented with the opportunity to figure out creative ways to include physical functions into the build. During this process, we found that it was possible to make all the controls interactive. My attention then shifted to trying to replicate the haptics of the actual hardware. I started to focus on each of the controls, the buttons, dials and power switch — testing different versions of the build to find the closest simulation of the sensation of holding a real Game Boy.The studs on the D-pad are included for two reasons:1. We like to include studs to add LEGO DNA, so you can see it is a LEGO model.2. That combination of LEGO bricks (with the studs showing) allows the D-pad to be able to tilt as it does on the real Game Boy. Recessing it into the LEGO Game Boy and adding tiles to cover the studs was one of the possible design choices, but that would remove the functionality.GameSpot: Are the buildable cartridges the same size as actual Game Boy games? If so, can the cartridge slot hold real games?LEGO: Unfortunately not. The real Game Pak is slightly too big to fit into the LEGO Game Boy set.Lego's building set is a near 1:1 recreation of Nintendo's Game Boy DMG.GameSpot: Were Link's Awakening and Super Mario Land always the cartridge choices, or were other games in the running? What's your personal favorite Game Boy game?LEGO: After looking at several different games, we landed on these two first-party games to celebrate our longstanding partnership with Nintendo.Link’s Awakening is my personal favorite Game Boy game. I have a vivid memory of calling the Nintendo hotline for some help getting the Hookshot while playing it.GameSpot: What's the smallest detail on this set that you're most proud of? What was the biggest challenge you faced?LEGO: I used all my powers as both a veteran LEGO designer and a lifelong LEGO fan to make this set as excellent as possible, so there are lots of favorite things to choose from. If I have to pick just one... it has to be the power switch function. While working on this set, I focused on replicating all the haptics of the real Game Boy as closely as possible. I tried to make all the buttons press-able and the dials turn-able, but getting that power switch to slide and click like the real one... that is my favorite feature.The biggest challenge I faced was trying to replicate the dimensions of the real Game Boy. The closest LEGO dimensions to the form factor of the real Game Boy are: 11 studs wide by 18 studs long by 3.6 studs deep. Dimensions for LEGO Bricks tend to be in even numbers, so finding the right combination of elements to put the screen and screen surrounding in the center of the device was a real brain teaser.GameSpot: Besides the Game Boy, what's your favorite LEGO Nintendo set?LEGO: It has to be the LEGO Super Mario Desert Pokey (71363). I love this set, it is so amazing how well it replicates the interaction with the Desert Pokey from the Super Mario games in real life.The Lego Game Boy includes three lenticular screen panels.The Lego Game Boy is the eighth officially licensed Nintendo building set designed for adults and the second to release in 2025. In May, Lego launched a very cool 1,972-piece Mario Kart display model for $170.Retro Nintendo fans should also check out the Super Mario World: Mario & Yoshi Lego set. This 1,215-piece model is built to resemble the Super Nintendo's 16-bit pixel art. The interactive sprites of Mario and Yoshi look fantastic. Released exactly one year before the Game Boy, Super Mario World: Mario & Yoshi retails for $130 but is on sale for $105 at Amazon.