No, I don't think the first rider is a savior at all. He's the crown wearing 'hero' riding in on a white horse as if to save us with his jabs, but is really after conquering us.

The first horseman is carrying a bow, like for shooting arrows. Illustrations of the four horsemen from the year 1000 to today depict him carrying a bow for shooting arrows.

The bow/rainbow is different. It was a sign God gave us of His covenant that He'd never again bring a flood upon the Earth.

John the Revelator wrote Revelation on the island of Patmos in Greece. The Greek word bow/Toxon is where we get our words Toxin and Toxic.

toxic (adj.) 1660s, from French toxique and directly from Late Latin toxicus "poisoned," from Latin toxicum "poison," from Greek toxikon "poison for use on arrows," "pertaining to arrows or archery," and thus to a bow, from toxon "bow."