Undertone

Undertone is Ratchet's Minicon and partner. Undertone and Ratchet teamed together to capture criminals until they were sent to Earth.

History
In Decepticon Island (Part 1), after the rebirth of Cybertron, Ratchet was given the task of patrolling space and capturing any rogue Decepticons by the Council, who weren't enamored with the Autobots. To aid him in his task, he was partnered with Undertone. The duo tracked a Decepticon to Earth, where they ran across Clampdown and Bumblebee's Bee Team. Undertone followed Ratchet back to Bumblebee's scrapyard base, where they encountered Toolbox. Undertone came along with Ratchet to take part in the raid on Glowstrike's Decepticon base. The team slipped into the base by masquerading as Grimlock's captives, although they were eventually spotted and surrounded by Steeljaw's new army of Decepticon fugitives.

In Decepticon Island (Part 2), the team had to split up, buying time for Bumblebee and Optimus Prime to detonate a cryo-gas bomb in the ship's ventilation. In order to rescue Windblade, Undertone and Ratchet fought alongside Drift and his Mini-Con students against Overload, but the Decepticon got beyond him, and he wound up getting thrown in a stasis pod. Jetstorm and Slipstream released Ratchet and Windblade who managed to take out Overload as they threw him in a stasis pod. Windblade freed Undertone from his trapped pod and the Autobots escaped the ship after Bumblebee and Optimus detonated their bomb. In the aftermath, Undertone opted to accompany Ratchet back to Cybertron to confront Cybertron's government.