The Known World, Turn 9
Topographic map of the world, detailing terrain effects
|Formal run||2 October–24 November 2010|
Ab Antiquo was an "experimental" Imperium Offtopicum game set in the Ancient Mediterranean (Europe, North Africa, and Western Asia) created and managed by taillesskangaru. It was the first pre-industrial spin-off and the first game to implement set victory conditions. Ab Antiquo served as the blueprint for the Iron and Blood series, both in terms of rule structure and the popularization of a separate sign-up thread.
Sign-ups started 22 September 2010, and the game began 2 October. It lasted for nine complete turns before taillesskangaru placed it on suspension due to poor health, then cancelled it on 24 November over dissatisfaction with its overall structure.
Applications to the game were limited to the sign-up thread, after which no new players would be accepted. There was no numerical limit on sign-ups, but the number of initial players would be capped, with remaining applicants placed on a reserve list. Updates aimed for 2–3 days and no sooner than 48 hours from turn's start.
Ab Antiquo used a provincial map, labelled for ease of reference. A player joined by selecting a capital province. Each turn of peace, a player could expand into three contiguous territories. Overseas claims were originally limited to provinces bordering an adjacent sea zone; on Turn 4 this was expanded to two zones.
Overlapping claims resulted in a contested province, which provided no income. Ownership was settled between the affected players, either through agreement or armed annexation. Provinces could be traded between players at any time.
Income was province-based, with each territory generating a certain amount of wealth per turn. Income could be increased by upgrading individual provinces, at a cost of one unit less than the next level, to a maximum of 20 levels. Wealth was not banked, but could be traded to other players.
Beginning Turn 4, upgrades were capped at two levels per province per turn. Forts were abolished and their defence bonus merged into an amalgamated Province Strength.
Military units were tracked on the map and could normally move one tile per turn. Each player had an Army and Navy Quality value that determined overall effectiveness, purchasable for 1 Income each. At game's start, this also represented the levy limit per turn: creating a new unit cost 10% of the current Quality level, and disbandment or defeat in battle lowered Quality by 20%. On Turn 4, Military Quality no longer depleted and units were instead given an Income cost equal to the number of provinces held. Units incurred an upkeep cost of 2 times the number of active units, minus 1.
Until Turn 4, a right of passage agreement allowed military units to pass through foreign provinces. Attacking from foreign land would conquer the province for the host if the player did not have a requisite link to one's own capital.
Land armies were the primary offensive force used to defend and conquer provinces. Upon creation, they gained one of eight specialized traits that provided specific combat bonuses. Only one army could occupy a province at a time, but friendly armies in adjacent provinces provided support in battle.
Armies could cross sea zones to attack any coastal province within the same turn at a 25% strength penalty (unless designated Amphibious), provided the attacker's and/or an ally's territory provided a coastal supply chain and no enemy fleets were present. Embarked armies were defenceless against dedicated naval units, and unescorted landing parties would be destroyed if intercepted.
Fleets were used for naval zone of control, either to block seaborne invasions or combat rival navies. Unlike Armies they could be stacked, and friendly and neutral navies could share a sea zone. Fleets could only move into a zone bordered by a friendly coastal province.
Forts were defensive emplacements available until Turn 4, that could be constructed in a province for 1 Income plus the number of existing forts within the province, up to a maximum of 20. Each fort provided a 5% bonus to defending unit strength. They also provided a percent chance of preventing a victorious army from seizing the province, based on the formula x/(x+5)*100, with 'x' the number of forts. However, an invading army with more than double the defending Army Strength would overrun the Forts regardless.
On Turn 4, Forts were abolished and their unit defensive bonus was merged into a province's upgrade level as an amalgamated Province Strength.
Combat was conducted by theatre, comparing cumulative Military Strength, applying combat bonuses, and adjusting the final results by an RNG modifier of 0–50%. Defeated units were only destroyed if the victor's total combat strength more than doubled the loser's, or if the unit could not retreat to a friendly province.
On Turn 4 combat mechanics were modified slightly. Attackers had to specify which (if any) adjacent units would support a battle; these would not contribute to defence against rival invasions. Defenders in coastal provinces received support from armies in provinces bordering the same sea zone (if not blocked by enemy fleets).
In addition to eliminating all rivals, a player could claim early victory in one of two ways:
- Cultural victory was achieved through the accumulation of 1000 culture points, purchasable for 1 Income each.
- Conquest victory required the capture of a customized set of provinces PM'd to individual players. A later rule amendment hinted that cooperative victory was possible, but required a full military alliance, i.e. joint foreign policy; defensive pacts were insufficient for this goal.