Close Combat by Atomic Games was originally devised as a computer game version of ASL. Atomic Games had already developed several games for Avalon Hill, however, with Avalon Hill embroiled in a financial crisis that would ultimately lead to its demise, Atomic Games took what work they had completed, severed ties with the board game franchise and completed the game's development for Microsoft. The first three Close Combat games were notable, at the time, for being among the few games published by Microsoft. The final two games in the original series were, however, published by Strategic Simulations, Inc.