Rainmaker

The Rainmakers are Decepticons from the Generation 1 continuity family.

All the colors of the rainbow, except for one...

The Decepticons known colloquially as the Rainmakers are part of Shockwave's forces on Cybertron. Each one is a Seeker with a bright, single-color paint job. (The green member, Acid Storm, did find a more exciting palette.) They retain their original Cybertronic "tetrajet" alternate modes.

As their name implies, they can make rain. Acid rain.

Fiction

Generation 1 cartoon

When a group of Autobots (and Chip Chase) journeyed to Cybertron to fetch a cosmotron for a wounded Optimus Prime, Megatron sent the trio to make things difficult for our heroes with some acid rain.

Guess what? They failed. Divide and Conquer

Trivia

• The term "rainmakers" was originally used by Bluestreak as a colloquial description of their actions. However, repeated fan usage has turned this into a widely accepted name for the group, which was eventually made official as such by Hasbro's bio for Acid Storm.