The grandson of Justice Society member Commander Steel, Nathaniel Heywood was a historian before realizing that something was wrong with history. He ended up taking his concerns to the Legends, who enlisted him to help them fix time.
Ironically, he may be responsible for breaking it even more, as he has fallen in love with a Justice Society member and as a result of their relationship she has not yet returned to the 1940s to have her children and live out the rest of her life.
Billionaire tech mogul Ray Palmer moved to Starling City, started dating Felicity Smoak, took over Oliver Queen’s company…and managed to NOT be hated by everyone in the fandom because he was just so damn charming.
When time came for Oliver and Felicity to get back together, though, Ray had to be pushed out, and after an apparent death which turned out instead to be an industrial accident that gave him powers, Ray joined the Legends.