Blue Nile Ties
Blue Nile Ties is an Imperial Age Ethiopian Mountain Monastery technology that improves Mercenary recruitment. It requires the Arab Alliance and reduces both the Coin/resource cost and training time of Mercenaries by 15%, making it relevant to repeated hiring rather than a single fixed shipment.

Research profile
- Age
- Imperial Age
- Civilization
- Ethiopians
- Research location
- Mountain Monastery
- Prerequisite
- Arab Alliance
- Research time
- 30 seconds
- Effect
- Mercenary cost and train time -15%
Effect & research conditions
The research takes 30 seconds and costs 500 Influence. Ethiopians must select the Arab Alliance and reach the Imperial Age before researching it at the Mountain Monastery. The 15% discount applies to Mercenary cost and training time; it does not improve their hit points or attack statistics. Its total return depends on the Mercenary units trained after the research completes.
Research condition
Ethiopians; Imperial Age; Arab Alliance; Mountain Monastery; 30 seconds; 500 Influence; Mercenary cost and training time -15%.
When to research
Research it when the army expects to hire enough Mercenaries for the 15% savings and faster queue to offset the Influence and delay. A player planning only one small recruitment may get more immediate value from another alliance option. Secure the Mountain Monastery during the research and prepare the resources and production route needed to use the discount.
The discount compounds across repeated recruitment
Blue Nile Ties does not deliver Mercenaries when the research completes. Instead, later eligible recruitment costs less and trains faster. The more units the player hires after the upgrade, the more opportunities there are to benefit from both reductions. Keep the discount separate from any direct unit shipment.
Alliance and age requirements
The Ethiopian player must choose the Arab Alliance and advance to the Imperial Age to reach the Mountain Monastery option. Influence is the research cost. Check the alliance decision early if a Mercenary-based plan depends on this late-game technology.