Antike Duellum – previewed at Spiel 2011 under the name Casus Belli – is a two-player strategy game based on modified rules from Mac Gerdts' Antike. The game includes two scenarios: Punic Wars (Rome vs. Carthago) on one side of the board, and Persian Wars (Greeks vs. Persians) on the other. The goal of the game is to be the first to gain nine ancient personages (Kings, Scholars, Generals, Citizens, Navigators).

Examples of modified rules from Antike:

• Modular layout - when a player founds a city, he chooses whether it produces Iron, Marble, or Gold
• Over 20 event cards, which provide more variety in the game
• Town walls for individual protection of cities
• Each "Know-How" costs a different amount - for example, inventing the market is more expensive than inventing the wheel
• A new Know-How for trading goods with the bank
• Higher costs for legions and galleys - they are first recruited from the bank to the personal supply (paying gold)
• Easier rules for conquering cities with no movement of units

Resource chips (Marble 18, Iron 18, Gold 18, Coins, 14) 46 cards.

• 24 tokens of value "1" for marble (8), iron (8) and gold (8)
• 18 tokens of value "2" for marble (6), iron (6) and gold (6)
• 12 tokens of value "5" for marble (4), iron (4) and gold (4)
• 14 coins