Alliance Tech
Alliance Tech is very important in building a strong alliance. Alliance Tech provides buffs such as marching speed, gold gathering, and damage recovery.
If you lose a territory (e.g. from territory war or server transfer), you will lose the buffs from previously claimed altars. However, you will never lose the Alliance Tech (even if you lost the Central Fortress!)
If you are an R4 or R5, send out regular reminder and ask your members to do Tech donation. Mark the tech you want to focus on with a star so that the tech can complete faster.