Buffaloids are a Cybertronian sub-species from the Aligned continuity family.

More properly known as a "Bisonoid". Science.

Bulky, strong, and fast, Buffaloids would be unstoppable juggernauts if not for their low intelligence, leaving them easily confused and susceptible to outside manipulation. As a result, they require someone else to do most of their thinking, and if nobody's around to give them orders then they feel lost and alone. Their durable physique means that they can easily smash through walls or charge unwary targets.

Fiction

2015 Robots in Disguise cartoon

The Buffaloid Terrashock was hired by Contrail as his private enforcer, and was later imprisoned aboard the Alchemor. After the ship crashed on Earth, his damaged stasis cell was recovered by humans and placed in a museum. When Terrashock awoke, he rampaged through the museum and easily trounced Bumblebee and his team before escaping onto Crown City's highways. Terrashock was intercepted by Bumblebee's team, who had formulated a new plan to take advantage of his need for directions, and was eventually incapacitated and recaptured. W.W.O.D.?

IDW Robots in Disguise comic

Another Buffaloid by the name of Overhead was also imprisoned aboard the Alchemor. Unusually for a Buffaloid, Overhead was a cunning criminal mastermind who secretly ran the gang known as the Cybercomrade Sect. Overhead's plan to build a Space Bridge was foiled by the Bee Team, along with the help of Ultra Magnus and several old Team Prime members. Robots in Disguise #4