In most universal streams, Chromedome is a comparatively quiet academic. Originally a number-cruncher at Cybertron's Institute for Higher Programming working on ways to improve the processing power of the Transformers' computerized minds, Chromedome found himself forcibly dragged into the Great War when a Decepticon attack destroyed the facility. Chromedome put his work to use programming Autobots so they could outsmart their Decepticon foes, but alas, only wound up fostering an intellectual arms race of sorts, in which both sides competed to repurpose the newest advances in programming into military advantages. Ground down over the years by this inevitability, Chromedome has come to accept that war with the Decepticons cannot be prevented—but only won.
In some universes, Chromedome is binary bonded to the egotistical Nebulan Stylor, who is more concerned with the finer things in life than intellectual or military pursuits. As such, the two occasionally clash, with Chromedome trying to get Stylor to be a little less superficial, and Stylor trying to bring out Chromedome's more social side, but generally speaking, they get along quite well despite their differences.
As a quiet 'bot of the mind, Chromedome has a tendency to fade into the background, but there also exist universal streams in which he has foregone science and taken to the front lines of battle to become a much more prominent figure. The Chromedome of these worlds is barely recognisable as the reserved scientist of those more well-known realities: instead, he is a hot-headed youth burning with an incredible passion for justice who even serves as Fortress Maximus's trusted, if impulsive and occasionally-irrational, second-in-command.
Sometimes he is also known as Tumbler.
His alt-mode is a Cybertronian Sports Car.