The two games under this name are both linked to Zimag, a small American company that planned to sell Atari 2600 games in 1983. Immies & Aggies, a marble-themed shooter, was listed in Zimag’s catalogue for spring 1983, but the company went out of business before it came out. A Mysterious Thief has you raid a four-storey building against the clock; this page runs a one-of-a-kind NTSC prototype that is now thought to come from Zimag or Vidco. Both are waiting below to be played in your browser.
A Mysterious Thief is a 1983 Atari 2600 game in which you play a burglar raiding a four-storey building against the clock. The version on this page is an NTSC prototype, and only one copy is known. The game itself did come out in Europe under other names, and it is now thought to be an American game by Zimag or Vidco. You can play the prototype here in your browser.
Immies & Aggies is a 1983 shooting game that the small American company Zimag planned to sell for the Atari 2600 but never released. The name comes from marbles: “aggies” are agate marbles, and “immies” are glass marbles made to look like agates. On screen, though, the marbles are simple coloured squares. What survives is a prototype, and it plays more like a rough experiment than a finished product. It is still an interesting look at what a small 1983 publisher had in the works. You can play it here in your browser.