ROKR

The same parent company as Rolife, aimed at a different person. ROKR builds mechanisms: gear trains, spring motors, hand cranks, marble runs. Parts are press-fit or mortise-and-tenon, so glue is rarely needed, and difficulty runs on a 6-point scale rather than 5. The pattern across the range is that the build does not end when the last piece goes in. Gears bind, marbles stall on ramps that need a genuinely level surface, cuckoo chimes come out mistimed. Robotime publishes fix guides for several of these, which tells you how common it is. Reviewers advise sanding and waxing parts before assembly, and the wax stick is often removed by customs. Instructions are picture-only with no written steps. Quoted build times run short: the Magic Piano lists roughly four and a half hours, and a hands-on reviewer needed over seven.