Black Thunder is a Bull that Ambush battled in the movie. Black Thunder was the 2019 runner up in the baddest of the bulls competition. Black Thunder is possibly 2000 pounds and (much like every bull) is aggressive against robots.
During its fight against Ambush, the bull seemed to be at a disadvantage at first.
Its initial charge was stopped by the robot who grabbed it by the chest and lifted it, the bull's rear kept going forward and its balls crashed against Ambush's knee. The bull didn't have time to regain footing and was slammed to the ground but the bull wasn't done yet, got up quickly and took some distance as Ambush was showing of to the crowd.
Its second charge was dodged by Ambush who jumped over the bull and stepped on its rump before landing.
The bull quickly turned back and charged again, only to be met with a solid punch to the face that sent its whole body flying backward and once again slammed to the ground.
The bull's defeat seemed certain but as Charlie was distracted flirting with a girl in the crowd, the bull had got up again and used the opportunity to charge once again.
Charlie noticed, but too late and Ambush's leg was tore apart by Black Thunder's powerful horns. The bot fell on the ground and it was the bull's time to show off as it threw the robot's leg into the crowd then he charge again after Ambush had managed to stand up.
The charge hit its mark and Ambush was thrown flying into the fence.. Charlie's protest were met by laughter and cheers from the crowd and his robot was gored through the chest, then lifted by the bull parading in the ring with the robot's body and finally thrown away with a mighty swing of the neck which resulted in Ambush breaking its neck as the robot crashed on the ground and was subsequently destroyed.
Black Thunder then joined back its pen.
- Black Thunder is the only robot challenger that is not a robot himself.