Sometimes other empires will seek your assistance in some matter, such as a request for resources or to attack an enemy. When a mission comes in, you can choose to complete or reject it within the time limit shown (note - you won’t be able to reject the mission once the countdown passes the halfway point). Failing to complete a mission or repeatedly rejecting missions will hurt your standing with the empire making the offer, while accomplishing the mission will raise your standing with them and possibly provide some other reward.
You may also offer missions to other factions once you’ve researched the appropriate technology from the Diplomacy research tree. To issue a mission, select the faction you want to work with and then click the Offer Mission button. Select the type of mission you wish to offer, the target faction and the other required details via the Change Level button.
The mission text is very specific about both the task to perform, and the time you have to complete the task. There is a lot of research options you can preform to change the time it takes to complete a task or to reduce the amount of negativity for failing to complete a task as well. It is very common for when your empire is growing that two of your allies will be at each others throats. And they will open diplomatic relations with you to assault one another. Or perhaps another has tasked you with a mission that you simply cannot preform, you can decline these missions to receive a small relationship decrease instead.
You can demand your allies for a sum of Credits, Metal, or Crystal to increase your economy or perhaps the other way around if an ally is in need of assistance. To complete the mission successfully, send them the required resources as a gift before the time limit expires.
Another mission type is to hire one of your allies to destroy a portion of your opponents fleet or structures. The target is very specific and the amount of ships/structures can also be set to the desired amount. When assigned to destroy structures it can be chosed to destroy either Logistical or Tactical.