This was an Allied cover and deception plan for ‘Carbonado’ (1945).
The undertaking was schemed for security purposes as an alternative to 'Rashness' so that both could be discussed by the Chinese staff, which was notoriously 'leaky' about security, without knowing which was the real plan.
After the Japanese 'Ichi' operation drew to a close, the Japanese went over to the defensive in China. The overall strategy then developed by Lieutenant General Albert C. Wedemeyer, the commander of the US forces in China and chief-of-staff to Generalissimo Chiang Kai-shek was to launch an offensive in the latter part of 1945 with US-trained Chinese divisions to drive to the south coast of China, thereby liberating Hong Kong and Canton to free the Chinese at last from dependence on the trickle of supplies over the mountains from Burma by air and road. This plan was originally codenamed 'Beta', but later became 'Rashness' and finally 'Carbonado'.
The US and Chinese forces appreciated the fact that it was obvious to the Japanese that the offensive would take place on the southern front because of the limited road network of China, the concentration of US-trained divisions in that area, and the known fact that information trickled freely from Chiang’s staff into Japanese hands. So US deception planners in Chungking, the nationalist Chinese capital, adopted an imaginative course. A pair of outline plans was prepared as 'Iceman' and 'Rashness' and given to the Chinese military council for the preparation of detailed plans: 'Iceman' was a drive to the east in the direction of Changsha with a diversionary effort in the south; and 'Rashness' was a drive in the south with a diversionary effort to the east toward Changsha. Only Chiang, his chief-of-staff General Chien Ta-cheng, and the war minister General Chen Cheng were told that 'Iceman' was the cover plan and 'Rashness' the real plan. The Chinese staffs working independently on the two plans did not know even that a cover plan existed.
From time to time, hints would be given to the Japanese that 'Iceman' had been selected as the offensive operation.
Events showed 'Iceman' to have been unnecessary. The Japanese began retreating in the south even before 'Rashness' (in its 'Carbonado' form') could be launched. Thus the Chinese offensive began with what was essentially to have been its second phase, and the war ended before even this could make much progress.