The 950-piece Bumblebee 2-in-1 Lego model is on sale for its best price yet at Amazon. Lego Icons: Bumblebee Transformers 2-in-1 (950 Pieces) $74 (was $90) | All-time low Lego Icons: Optimus Prime Transformers 2-in-1 (1,508 Pieces) Transformers fans can grab both of Lego's 2-in-1 Autobot building models for great prices at Amazon for a limited time. The 950-piece Lego Bumblebee is discounted to $74 (was $90), which is the lowest price ever for the popular display model. Earlier this month, Amazon was selling this set for $76, so the new deal is just a bit better. You can also get the Lego Bumblebee deal at Walmart. Meanwhile, the 1,508-piece Lego Optimus Prime is down to $157 (was $180). If Amazon sells out, the Optimus deal is also available at Target--though Target says the offer expires Saturday, October 25. If Target's deal does disappear this weekend, it's quite possible Amazon's price cut will follow. Optimus Prime and Bumblebee are part of the Lego Icons series for adult collectors and experienced builders. Bumblebee can be converted into his signature yellow car, and Optimus twists and folds into his famous red and blue truck. Lego recently introduced its first Transformers Decepticon 2-in-1 model. Lego Soundwave launched August 1 on the Lego Store before arriving at major retailers October 1. The 1,505-piece Soundwave Lego set retails for $190 and is the first model in the series with an electronic component. Check out everything you need to know about the Lego Icons Transformers series below. We included images of all three robots converting to their alternate modes. Optimus Prime is a highly detailed model of the Autobot leader's G1-era design. With 19 points of articulation, you can create an wide range of poses by adjusting his limbs in robot mode. Lego's detailed scale-model of the G1-era Optimus Prime is essentially a 13.5-inch action figure. You certainly don't want to be rough with it, but it has more movable components than you'd normally expect with Lego thanks to its 2-in-1 design. Switching from robot to truck mode and back again is a relatively straightforward process. At first, the switch might take you a couple minutes, but once you have the steps memorized, it's possible to convert the build in less than a minute. Beyond its ability to completely transform, Optimus has a suite of interactive features and accessories that make it one of the most dynamic builds in Lego's lineup of collectible sets for adults. Brick-built replicas of the ion blaster and Energon axe can be attached to his hands. You can easily fasten or remove his jetpack and swap between two different waist panels. The dual windows covering his chest can be swung open to access the Matrix of Leadership artifact. It also comes with an Energon cube and an information plaque to display alongside the model. Lego makes a ton of vehicle display models, so it's pretty remarkable that Optimus Prime's "secondary" truck mode looks good enough that you could mistake it as a vehicle that doesn't transform into a robot. When displayed as a truck, Optimus is 10.5 x 4.5 x 5.5 inches. Like many other Lego sets geared toward adults and collectors, Optimus Prime has a more complex build process than the average set. An ample variety of conventional bricks and unique piece types makes it a thoroughly rewarding set to construct. Depending on your experience with Lego sets of this size, it could take you anywhere from three to six hours to complete. After two years of talking to himself and converting into a truck to take long, aimless drives, one of Optimus Prime's pals finally joined him in the brick-built world of Lego last July. Since then, the 950-piece Bumblebee model has almost always sold within a few bucks of its $90 MSRP. Bumblebee doesn't have as many intricate details as the larger Optimus Prime and Soundwave models, but it's still a wonderfully designed building set that accurately recreates the popular Autobot's G1-era look. It's one of the coolest Lego models for adults that stays below the $100 mark. The 2-in-1 build can quickly morph from robot to car. Bumblebee's bright yellow vehicle resembles a Volkswagen Beetle from the 1980s. In car mode, Bumblebee is 8.5 inches long--not much smaller than Optimus in truck mode. Bumblebee's robot mode measures 9.5 inches tall. He has articulated limbs to create dynamic poses. Bumblebee's accessories include a large, detachable ion blaster and jetpack. The display plaque connects to a small buildable stand and lists Bumblebee's power stats. The latest Transformers Lego set marked the arrival of the Decepticons. Soundwave is a 1,505-piece, 13-inch display model, so it's roughly the same size as Optimus Prime in height and piece count. Like the other two Transformers builds, Soundwave is based on his appearance during the G1 era. Instead of transforming into a vehicle, this 2-in-1 build can be converted into a boombox. Fittingly, it has sound effects and lines of dialogue that can be heard by pressing Soundwave's play button. Another unique aspect here is that there are buildable figures of Ravage and Laserbeak. And just like Soundwave, these smaller figures can transform. After converting Ravage and Laserbeak into cassettes, they can be stored inside Soundwave's cassette deck. A brick-built information plaque details Soundwave's technical specifications (power statistics). A miniature cassette tape sits next to the reference card. Soundwave launched August 4 as a timed Lego Store exclusive before releasing at major retailers on October 1.