The new sensor-packed Smart Play Brick will land this spring as part of a special Star Wars collection. The update adds interactive lights and sound to the Lego experience—including the minifigs.

The most expensive Lego set to date, and the only one to nearly hit a four-figure price tag, will release next month, the toy company announced on Thursday, Sept. 4. The Ultimate Collector Series Death Star, inspired by the moon-sized space station from ...