The Imperial Japanese Army had been heavily featured in many Marvel Publications during its Timely Comics era of publication. Subsequently there is over 70 years worth of appearances of members of the IJA in Marvel books. This is an unabridged version.
For a full listing of members of the IJA on Earth-616 see See the full membership roster.
Baron Hitso's Kamikaze Missiles: These missiles were specially built with a human occupant inside. They could be piloted remotely or by the pilot inside. The missiles operated like small aircraft and could be redirected either by the remote console or the interior pilot. These missiles were all destroyed by Captain America and Bucky.
Dragon of Death: Commanded by Captain Osaki, it was the most massive under water vessel in the Japanese fleet. It was shaped as a large red Japanese dragon. Could swallow ships whole and has massive decks that contained labs, weapons platforms and more. It was sank by Captain America and Bucky off the coast of Hawaii. The vessel was then salvaged by the United States military until it was stolen by an early incarnation of Hydra. It was later destroyed by the Invaders in 1944.
Iron Clawed Monster: Was an undersea vehicle shaped after a king crab. It had large pincers that could rip metal to shreds. The Japanese planted the Iron Clawed Monster near an American navy dock to sink American ships before they could be deployed. The vehicle was discovered by the Patriot who destroyed it.
Agent X's Secret Headquarters]: The secret headquarters of Agent X was a massive battleship disguised as a mountainous island that patrolled the Pacific. It contained a hidden landing strip for aircraft and secret docking bay for Japanese battleships and submarines. The vessel was destroyed by the Human Torch and Toro.
Submersible Icebergs: Created by General Tsaki these vessels were disguised as icebergs to trick their enemies. The vessels were lined with sharp edged below the water level to puncture and sink American ships. They were all destroyed thanks to the Sub-Mariner and the United States Navy.
Admiral Footsu's Super-Sub: Constructed on Kobe Island. It was a massive submarine that was over 1000 feet in length. It had three turrets, two smaller turrets armed with six cannons, and one larger one armed with twelve cannons. Other than the additional cannons and greater size it did not appear to have any additional enhancements. It was destroyed by the Sub-Mariner.
Dr. Yokotio's Sea Dragon: Was a submarine that in the likeness of a sea dragon. It could move very quickly, dive in and out of water, and had a massive mouth cavity that could seriously damage ships. One serious design flaw was that it was incredibly easy to flood as the mouth compartment could not be open while submerged. It was sunk by Captain America and Bucky.
Mikado's Super-Shell: A massive artillery cannon build by the Japanese in 1942. It's construction was overseen by the Paw. Upon its completion he device was capable of launching massive explosive shells a great distance. It took advantage of the upper atmosphere to launch its missiles across the Pacific to strike American targets. The cannon would initially launch the rockets high into the stratosphere where timed explosives would go off sending the shells crashing back down to Earth on the other side of the ocean. The massive cannon was destroyed by Captain America and Bucky in Captain America Comics #18.
Dr. Nichi's Flame Bomb:
Nichi had developed a specially made torpedo that used "electrolysis of water" to split hydrogen from water molecules. This caused a terrific heat that created a blue flame that was also fueled by the hydrogen found in the water, causing a massive flame that could destroy an entire convoy of ships. The amount of blue fire created appeared to be limited by how long the torpedo's generator could operate. The Sub-Mariner prevented these from wide use against American convoy in Marvel Mystery Comics #62.