Conversion is the process of changing a unit or building's allegiance to your team. This is different from Capturing, that happens in some units, not just those eligible for capture.
The time it takes to convert a unit in seconds randomly varies between 75% of the units conversion rate to 100% of the conversion rate. For example, a Greek Priest has a conversion rate of 10. Therefore units will take 7.5 to 10 seconds to be converted.
Some units have a conversion resistance, which multiplies the amount of time it takes. Multiple priests do not convert a single target faster.
Converting a unit with a garrison capacity, such as the Babylonian Siege Tower, will not convert all units inside, they are instead ejected instantly.
The only unit that can convert buildings is the Priest of Ptah. Some buildings are always immune to conversion.
Babylonian Ox Carts can be converted and used by any civilisation, even though they serve as a mobile version of the storehouse building.
Most ships can't be converted, but Fishing Boats can be converted by the Priest of Ptah. Guardians and certain special units like the Norse Chief, Primus Pilus and Aquilifer are immune to Conversion as well.
Units converted from a different civilisation will lose any gear that was originally equipped, making them significantly weaker at higher levels. Units converted from the same civilization (or converted back to their original civ) are instead updated to the new owner's gear loadout. Villager units will not be able to build any building unique to their original civ or their new owners, or even any building that isn't available to both sides (For example, a Babylonian villager converted to any other civilization can't build any walls, as Clay walls are only available to Babylonians, who can't build Stone walls).
Converted units will retain Champion upgrades and share the benefits of common shared upgrades with the new owners regular units (ie Armory technologies), but tend to lose out on other upgrade effects from both their original owner and the new one.
Units that can convert units[]
 |  |  |  |  |
| Priest (Greek) | Priest of Ptah | Magus | Augur | Priest (Babylonian) |
 |  |  |
| Seer | Rhapsode | Pontifex |
Upgrades that can affect conversion[]
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| Divine Vision | Sight of the Sun | Without Number | Code of Hammurabi | Pax Deorum |