The Combined Beast-Warrior BullTaurus (騎獣合体ブルタウロス) is the hulking battle robot of the Black Knight from Seijuu Sentai Gingaman (1998). At its core is the Heavy Starbeast GoTaurus (剛星獣ゴウタウルス) – the only Starbeast of the series that is fully metallic from the outset. Hailing from the distant planet Taurus, GoTaurus serves as the loyal partner of the Black Knight (Bulblack, and later Hyuuga). In the US adaptation Power Rangers Lost Galaxy, GoTaurus becomes the Torozord, the Zord of the Magna Defender.

GoTaurus marks a genuine first in Sentai history: it can channel its power into the Black Knight, enlarging him into the giant Heavy Knight BullBlack (Mega Defender in Lost Galaxy) – making it the very first mecha ever to grow its own partner-warrior to giant size and fight alongside him. On the command "Knight-Beast Combination" (騎獣合体), GoTaurus takes Heavy Knight into itself and rears up onto its hind legs: the forelegs become arms, the neck swings upward to reveal the head, and the 45-meter BullTaurus is complete. For a weapon, both Bull Swords merge into a single Twin Bull Sword, which it uses to unleash its finisher, the "Bison Fierce Cut." In the US version this robot mode is called Defender Torozord and wields the powerful Defender Axe or a double-bladed lance.

DX toy: Bandai Japan released the DX BullTaurus in 1998 as part of the Gingaman line – a hefty die-cast chogokin that converts between a powerful bull mode and an upright robot mode, and includes the matching Black Knight figure to ride atop or integrate into it. An expanded "DX BullTaurus Daikessen (Decisive Battle) Set" additionally bundled the Knight Axe along with the coveted "Beast Armor Shine" armor parts, letting collectors upgrade the separately sold DX Gingaioh into the gold-clad Super Armor Shine Gingaioh (超装光ギンガイオー) – a completist's dream.

Stateside, 1999 brought the Deluxe Defender Torozord from Bandai America (with a suggested retail price of around $9.99 at the time), which likewise transforms from bull mode into the knight-robot mode and includes the Magna Defender figure – today a sought-after Lost Galaxy collectible. In 2025, Bandai reissued the full combination as a high-end SMP (Shokugan Modeling Project) "BullTaurus & Galaxy Decisive Battle Set" through Premium Bandai – a model kit including BullBlack plus Beast Armor Shine parts for SMP Gingaioh and Victory Mars.