WWII was an era of rapid military technological change — a different world every year. The 25-ton Panda was the world's strongest tank in 1939, but only two years later, in 1941, it faced new challengers: the Soviet Union's legendary T-34 and its German relative — the Panzer IV, now armed with a 75mm/L48 gun. By 1942, the American M4 also entered the fray. But the greatest challenger came from China itself.

This was the Cloud Leopard, developed by the old rival from the Tianjin Design Bureau — the former Southern Guangzhou Branch, Second Bureau.

Gao Bupang's Panda had stolen his "colleagues'" livelihood, bringing the design bureaus' covert competition into the open. Chen Ke himself had the idea of splitting the tank design establishment in two, fostering healthy competition to select the best. Under Chen Ke's authorization, the Guangzhou branch was spun off after the "Panda Incident" and elevated to equal status with the Tianjin Design Bureau.

After the Panda entered mass production, the Armored Forces Committee barely had time to celebrate before Chen Ke — "whipping the fast horse" — put forward the design specifications for the next-generation main battle tank: a 30-ton design. Requirements: mobility approaching or matching the Panda; a larger main gun — a 90mm/L50 tank gun; 30 tons as the starting weight with no upper limit; ability to effectively resist the Panda's 76mm/L40 main gun at 500 meters.

By 1939 standards, this specification was slightly premature. Both the Tianjin and Guangzhou bureaus were thrown into chaos — neither the engine nor the 90mm tank gun existed beyond blueprints, and the manufacturing difficulty of a 30-ton-class tank was incomparable to ten- or fifteen-ton vehicles.

The 30-ton tank design was no longer something two design bureaus alone could accomplish. It required the entire industrial system working in concert to advance the technology — but for socialist China, this was not a problem.

Fortunately, the 550-horsepower diesel engine prepared for the 30-ton tank was developed smoothly, passing testing successfully in June 1939. The new 90mm tank gun was also completed on schedule. By the time the European war expanded fully in 1940 and Germany invaded France, both the Tianjin and Guangzhou bureaus had produced prototypes mounting the 90mm gun.

The Tianjin bureau's prototype weighed 37 tons empty; Guangzhou's weighed 34 tons. Both used the same gun and engine. The key difference: the Guangzhou bureau adhered to the traditional rear-mounted transmission design, while Tianjin used a front-mounted configuration.

The result: Tianjin's tank sat 30 centimeters taller than Guangzhou's. Meanwhile, Guangzhou's design suffered from difficult gear shifting, imposing greater physical demands on the driver. Driving convenience and crew comfort were inferior to the Tianjin design.

Ultimately, the lighter, more mobile, and structurally simpler Guangzhou design won the competition. Tianjin's chief designer Gao Bupang was deeply displeased, suspecting backroom dealings — because Guangzhou's chief designer, Lin Pingzhi, was the son of Standing Committee member Lin Shenhe, and Gao alleged he had influenced the Armored Forces Committee's evaluation through his father.

Regardless of Gao Bupang's dissatisfaction, Guangzhou's product won the bid and received the designation "Cloud Leopard" — adding another member to Chen Ke's "Armored Zoo."

But fortune struck from an unexpected direction for the defeated Gao Bupang. The disgruntled designer brought his complaint to Chen Ke. After hearing Gao Bupang out, Chen Ke privately convened an internal Politburo meeting. Afterward, he offered new advice: "Package your design drawings and prototype and sell them to the Germans!"

Under Chen Ke's encouragement, the Germans obtained the Tianjin bureau's complete design package and a prototype tank (smuggled through Turkey) at the "cabbage price" of 2 million gold marks. Gao Bupang himself even traveled to Germany to collaborate with Dr. Porsche on developing the German version of the 30-ton tank. To prove his superiority over Guangzhou's Lin Pingzhi, Gao Bupang suggested to Hitler that the German 30-ton tank be named "Tiger" — a name Hitler loved and approved. The resulting vehicle, equipped with a German gasoline engine and an 88mm gun, became Germany's legendary wartime tank: the Tiger.

With China's help, the Germans were fortunate enough to break their bad habit of "wasting tonnage" in tank design. To Gao Bupang's frustration, however, the mad Dr. Porsche — under the equally mad Hitler's demands — transformed the German version of the "Chinese Tiger" by sacrificing mobility for defense, ballooning its weight to 43 tons. Defense increased dramatically while mobility deteriorated catastrophically.

When the Soviet-German war erupted and the Red Army encountered the German Tiger's formidable threat, they simultaneously rushed to develop the T-34/85 and demanded Chinese Cloud Leopard tanks as aid. The Chinese Leopard and German Tiger — two tanks both developed by China — began another kind of competition on European soil through actual combat.

The "Chinese Leopard" was balanced across offense, defense, and mobility — strategically and tactically outstanding in maneuverability, always appearing wherever needed. The "German Tiger" was thick-skinned and tough, and combined with the excellent quality of German tank crews, its combat loss-exchange ratios surpassed the "Chinese Leopard."

Commanders preferred the former; regular tankers loved the latter. Which was superior remained a matter of debate. Surviving armored troops on both sides praised the opposing tank: German tankers envied the "Chinese Leopard's" outstanding mobility and high sortie rate, while Soviet tankers envied the "German Tiger's" thick armor — during the war they even developed the Stalin tank with armor thicker than the Tiger's.

The final chapter of the Chinese Leopard vs. German Tiger rivalry played out in the Middle East. After the Cold War began, Arabs armed by the socialist camp and Israelis armed by the capitalist camp both possessed large quantities of cheaply supplied WWII surplus weapons. The French, supporting Israel, sold all 200 of their captured German Tigers at scrap-metal prices to the Israelis. Meanwhile, the Škoda armory in Czechoslovakia shamelessly supplied identical German Tiger tanks and spare parts to both sides. Of course, the postwar victors were no saints either — Chinese Leopards, T-34/85s, and M4 tanks also appeared frequently on this land flowing with black gold beneath their treads.

On the European Soviet-German front, the Cloud Leopard performed brilliantly, even earning the title of WWII's best medium tank. But on the Asian front, its position was challenged by the "old" tank it had nearly replaced — the Panda.

On the scorching Asian battlefields, the Panda defended its significant position through superior mobility. But every appearance of the Cloud Leopard struck terror into British and American tankers, firmly securing its position as alpha predator — not surpassed until the superior "Elephant" arrived at war's end. Before the Centurion and M26 appeared in the war's later stages, every Cloud Leopard sighting triggered similar panicked radio calls from British and American tank crews:

*"Leopard, leopard! Chinese leopards coming down from the hill on the other side!"*

This commonly heard cry from their opponents sufficiently illustrates the Cloud Leopard's historical role and status. The British and American universal designation for it was simply "the Leopard" or "the Chinese Leopard."

With the devastating power of its 90mm/L50 tank gun, the Cloud Leopard could achieve near-certain one-hit kills against all contemporary British and American tanks within 1,000 meters. On the battlefield, the Cloud Leopard's greatest enemies were the British Comet (armed with a 17-pounder) and the Firefly tank destroyer, as well as the American M36 tank destroyer mounting a 90mm gun. The first two could pose serious threats within 700 meters; the latter's firepower matched the Cloud Leopard's, capable of destroying one within a kilometer. But all three had significant drawbacks, and none matched the Cloud Leopard's overall performance.

The Cloud Leopard's emergence triggered a "Leopard crisis" — much like the earlier "Panda crisis" — and combined with the "Tiger shock" from Germany, these three events were later humorously dubbed "China's three armored impacts on the Western world." Britain's famous Centurion and America's M26 were emergency developments specifically designed to address the Leopard crisis.

After winning the competition, the Cloud Leopard was rapidly put into mass production, exceeding 20,000 units total during WWII. Apart from a small portion supplied as foreign aid to allies, the remainder equipped China's rapidly expanding armored divisions and strategic reserves.

Unlike the Panda with its vast family of derivative vehicles, the Cloud Leopard family was compact. Its combat derivatives included only the "Iron Leopard" mounting a 155mm heavy howitzer and the "Flying Leopard" with twin 37mm AA guns. There were also variable numbers of Cloud Leopard chassis-based bridgelaying and recovery vehicles. Per the Universal Chassis Specification, these derivatives were typically assigned directly to Cloud Leopard-equipped armored divisions for integrated operations — also to reduce front-line spare parts logistics pressure.

The Cloud Leopard represented the fully mature product of China's WWII tank design. Although a series of improvements and refinements were made after its debut, the overall vehicle changed little from start to finish. The A through D series involved only mechanical adjustments and refinements, with modest armor increases. Near the war's end, the E series was developed with a new turbocharged diesel engine boosting power to 600 hp for even better mobility — but by then the war was nearly over, and only two armored divisions' Cloud Leopards were upgraded to E-series standard.

The Cloud Leopard's greatest European adversary was the German Tiger — which was, ironically, the product of its Chinese competition rival being "married off" to Germany. It was the only tank with legitimate claim to compete for the title of WWII's finest.

On the Asian front, the Cloud Leopard's most formidable opponents were the British Centurion and American M26. But by the time these appeared, the Cloud Leopard had already rampaged across the battlefield for two full years. The Centurion and M26 ended the Cloud Leopard's "Invincible Loner" era — only for it to be the new generation MBT's turn: "Chairman Chen's Newest Pet," the "Elephant," striding forth to proclaim its supremacy across the land.

The Cloud Leopard was also used to develop a tank destroyer armed with the "Elephant" tank's 105mm main gun — similar to the Soviet SU-100. Designated the "Spotted Leopard," only four prototypes were built for testing and technical reserve purposes. Since the opposition's armored capabilities were too weak — the Cloud Leopard's existing 90mm gun was sufficient to handle all adversaries — no further production was undertaken.

During the postwar Cold War-era Middle Eastern wars, both Israelis and Arabs were equipped with large numbers of Cloud Leopard tanks. The Israeli Cloud Leopards were mostly captured vehicles and Soviet-discarded WWII surplus. Initially, Israel clung tightly to the Soviet Union, which sold off Chinese-supplied Cloud Leopards at discounted prices. When Israel later shifted toward the Anglo-American camp, Soviet aid was cut off. During the First and Second Arab-Israeli Wars, the Cloud Leopard remained the best tank in Israel's armored forces. In the 1950s, the Israelis upgraded them with British-made engines and replaced badly worn guns with American-produced 90mm tank guns — the Cloud Leopard's final and most powerful variant. Similar upgrades were applied to their old adversary: the German Tigers that Israel had also acquired.