It included a cardboard-mounted, folding map of a local region of the Milky Way galaxy, a set of rules and charts, and the 352 counters representing the various spacecraft, ground units, and markers, and a six-sided die.

The Sun and nearby stars lie at the extreme edge of this alien space-faring civilization, and the Terrans struggle to survive and expand against this powerful state.

Each hex represents a half parsec, which would require about 1.8 years to traverse traveling at 90% the speed of light.

Only a dozen stars have naturally habitable planets, although many more have planetary systems with outpost-capable worlds.

The game includes a variety of ship types, ranging in size from the small scouts and fighters to the mighty battleships.

[1] The Terrans generally have stronger ships overall and have the upper hand on beam weapons, while the Imperium favors missiles.

Imperium was designed by Marc W. Miller,[3] developed by Frank Chadwick and John Harshman, and published in 1977 by the Conflict Game Company and GDW.

The game includes an economic system in which the units on each side are produced and maintained.

The Terran income is based on what type of world the player currently possesses, and whether it is connected by friendly jump paths to Sol.

The Imperial income on the other hand has a fixed budget, but an increment for each connected outpost and world.

[2] A "Glory Point" tally earned by the Imperium tracks who is having the upper hand in any given war.

The range between the amount required for Imperium or Terran victory begins to shrink after turn three, representing the decreasing appetite for continued hostilities.

There is also a system built into the game for production of new units, colonization, and other changes during the inter-war periods.

15), Tony Watson gave the game a strong recommendation, saying, ""Imperium brings together many common themes of science fiction, and ties them to an excellent and intriguing game system which places both players in a unique situation with unique abilities to respond to that situation.

"[10] In Issue 11 of The Wargamer, Hugh Baldwin liked the wide variety of options available to each player, writing, "A nice feature of the counter mix is the very wide variety of unit types for both the Terran and the Imperial player, ranging from Scouts, Destroyers, Missile Boats and four types of Cruisers ... to Dreadnoughts and Battleships, and including auxiliaries such as Transports and Tankers."

He liked the straightforward rules, saying, "It is a medium sized game of no great complexity which demands strategic attention and can be in doubt to the end.

However, Minch found the production values of the game components to be poor — the counters were too thin and not cut well, and the map contained errors.

"[12] In the December 1979 -January 1980 edition of White Dwarf (Issue #16), Colin Reynolds gave the game a rating of 9 out of 10, saying, "The whole is extremely well produced, boxed, with a colourful map and large, clear counters and simple, clear-cut rules.

Imperium is, without exception, the best game of its kind I have seen to date, and is a valuable addition to any gamer's library.

"[2] In the inaugural edition of Ares Magazine (March 1980), David Ritchie gave Imperium a better than average rating of 8 out of 9, saying, "This is either a serendipitous design or a cold-blooded development of a classic.

Irsik noted, "There are a dozen strategies about what to buy for your fleet and how they will be used, which gives this game good replay value."