The Japanese had many forces available in addition to those actually landed on Guadalcanal. Through most of the campaign, tens of thousands of troops on Rabaul in the Shortlands, and in other areas needed only a safe means of transport to enter the fray. The problem for Admiral Mikawa, on Rabaul. was providing that transport many units were sunk trying to reach Guadalcanal.

Because of the risk, others were never sent. In listing the additional troops available, numerous problems come up. The Japanese were not German-style record keepers, and American intelligence was not always accurate. Incomplete and contradictory unit identifications were always cropping up. Worse yet, often only a part of a unit was sent to Guadalcanal. Some would be left behind some would be sunk in transit and the elements actually arriving might arrive over a period of many weeks.

In trying to stay as close as possible to Avalon Hill's Order of Appearance. I had to contend with the fact that units given sometimes had no real existence or were far weaker than what is shown—but the extra factors helped represent a myriad of smaller units that couldn't be shown. the game has been divided into four reinforcement periods, showing additional troops that may be landed.  These additional units may be landed in accordance with the "Henderson Field" rules.