The huge expansion of Generation 1 designs in 1986 included a great number of combiners, most of which came from previously unused “Scramble City” Jizai Gattai designs. However, a totally new design was forwarded in the Predacons - a predatory animal themed team that deviated in some key ways: each figure was roughly the same size (as opposed to a larger leader figure), and that the figures are all quite large. Tantrum is a orange, red and gray robotic bull river buffalo of species Bubalus bubalis, with the horns unrealistically raked menacingly forward.

US Patent for G1 Tantrum


Tantrum was designed by Teruo Kitamura. His US Patent, titled Reconfigurable animal toy buffalo (aka Transformers G1 Tantrum) was filed on December 13, 1985 (U.S. Patent No. USD298563 S).


Tantrum transforms into a primarily orange robotic water buffalo with a red head, gray shoulder and hip armor, and red legs. He is decorated with large silver foil stickers that have dots suggesting riveted armor plates. His well-articulated head features a pair of large curved horns molded in hard rubber. Two large holes on top of his hips allows the included Predaking foot plate to be attached as a huge double-barreled back cannon. His transformation involves extending the robot legs down from the buffalo hips, and folding away the rear buffalo legs. The front legs fold down onto the robot's back, and the gray shoulder armor extends down to form the Popeye-like arms. The buffalo head rotates to reveal the yellow robot face on its bottom. Additionally, a small plate flips up to form the robot's chestplate. His robot mode is stocky and muscular-looking, and only adorned by some additional molded detail not seen in the rhinoceros mode. He can wield any combination of his gold sword and two black rifles in this mode. He can transform into the right leg of Predaking by pushing the robot legs up, tilting the head down, and folding the arms away. He can also form the left leg of Predaking, but the original version of the mold does not have a hole for Razorclaw’s leg clip on the opposite side (see Availability below).

Collector Notes

Tantrum’s stocky design makes him generally sturdy. However, the neck connector is comparatively weak, and the head can be forced upward when rotating it around over the raised edges of the torso's top surface causing it to break. The flip-up chestplate tends to loosen over time so that it will not stay up in robot mode, causing some collectors to display him with the plate down in robot mode, and up in buffalo mode Also, use of the horns as weapons against Autobots, dogs, and younger siblings can result in it being chewed and frayed.


Tantrum has two primary variations, like most 1986 toys. The earlier version has die-cast metal shoulder and hip surrounds, and the elongated raised area on either side of his sword blade was sharply defined by a sculpted indentation. At some point, the raised area was blended smoothly into the blade surface, and later in 1986 production switched to an all-plastic body. All versions of Tantrum feature a rubsign on the the buffalo’s back.


Tantrum was available worldwide (except the United Kingdom) in 1986. In Japan, he was available in a Predaking gift set in 1986. He was available in the US again in 1987. Tantrum was re-issued in Japan in 2004, nearly identical to the 1986 metal-bodied giftset version. He recieved a second Japanese reissue in 2010, branded with the “Welcome to 2010” logo. This version again uses the metal body, and features a redesigned sticker sheet, a gold face (instead of yellow), and metallic shades of his plastics. This version had a symmetrical connector socket to facilitate attaching as either Predaking leg. A similar version was released in the US in 2013’s Platinum Edition Predaking.

Redecos & Retools

Tantrum’s mold has not been re-used.