While not LEGO® products, Terraria and Starbound are two great side scrolling games with as much building as you could want in the genre. Starbound is 33% off on the Steam platform. Terraria has been ported to most consoles and handhelds, but the Steam version is both the cheapest and most up to date and fully featured version, currently 25% off. The Wii U and 3DS versions are also on sale.