A quartet of infamous warlords and master criminals who join forces with Iron Claw during the events of J.A.K.Q. vs. Gorenger. Though not originally part of Crime, they unite under a common plan to devastate Tokyo and expand their influence across the globe.

Operating from a massive flying saucer and commanding their own armies, the Big Four represent an alliance of veteran enemies powerful enough to draw the attention of multiple heroes beyond J.A.K.Q.

An iron-masked dictator who terrorized Europe before aligning with the Crime Big Four. He commands the Iron Mask Battalion and fights with a heavy shield, a battle spear, and a blowgun loaded with poisoned darts, making him both a battlefield commander and a dangerous front-line fighter.

A ruthless conqueror who once battled Gorenger in Africa before joining the Crime Big Four. General Sahara is portrayed as a disciplined strategist and skilled swordsman whose military precision makes him one of the alliance's most formidable field leaders.

An arrogant and calculating mastermind who commands the Crime Big Four's flying saucer. UFO Captain oversees the group's global movements and serves as the navigator and tactician behind their airborne operations.

A brutal tyrant from Mongolia who previously battled Kikaider before joining the alliance. Covered in skull-decorated armor and wielding a crushing iron ball and chain, Hell Boxer relies on sheer intimidation and savage close-range power to overwhelm his enemies.

The giant combined robot form created when the Crime Big Four merge their powers. This final war machine serves as the alliance's ultimate weapon before it is destroyed by the combined efforts of J.A.K.Q. and Gorenger.