Game rules
Reinforcements
From the Rally Point you can send troops as reinforcement to your other villages, your oases or other players. Reinforcements stay in the target village and defend it in every battle until they are sent back from the Rally Point.
ACS (joint attack)
To start an ACS, send an attack, raid or siege to a village with the ACS option enabled. Your other villages and your alliance members can join it from the Rally Point: their troops are slowed down to arrive with the leader and fight in the same battle, and each army gets its share of loot and losses. Oases cannot be the target of an ACS.
See also: Rally Point
Values for the Babylon server: speed x10, troop speed x5, production x4. Times are those with the building at level 1. Server Settings