Not the best title, but a run, in-terms of prototype collecting, is a series of items that link closely to a particular toy or character in varying stages of pre-production.
Here are a few examples:
L-R vehicle mode: Rodimus Prime painted test shot/EP, unpainted + bagged Hotrod test shot/EP, painted Hotrod test shot/EP, 'pink' Hotrod first shot with blue windshield (depicted on the top of each and every box), Targetmaster Hotrod Mock-up (drilled hands and, missing, engine - hardcopy Firebolt stood in the foreground), hand-painted Rodimus Prime hardcopy. The two Hotrod first shots and Rodimus Prime hardcopy sport mock-up stickers
L-R robot mode: unpainted Hotrod test shot/EP, first version 'pink' Hotrod first shot with clear windshield, Hotrod sample.
In case: hand-painted hardcopy Blurr with mock-up stickers, atop case: Targetmaster Blurr mock-up, robot mode: Blurr test shot/EP, L-R vehicle mode: test shot/EP vehicle mode Blurr, sample Blurr, test shot/EP robot mode Blurr.
The two EP Blurrs in bubble wrap differ in mode only, both are marked with "EP3" The third version of the engineering pilot stage for this toy. EP stands for "Engineering Pilot".
Here's a run that incorporates both a production and a mock-up Computron gift set, a first shot Computron with mock-up stickers, a Scattershot first shot, a Computron wax casting hardcopy, and a selection of hardcopy Technobot accessories primed in grey.
Who else has got the runs? Nah, still a rubbish title....