To accept reinforcements from other alliance cities, you need to build an embassy. The higher lvl of the embassy, the more troops u can receive.
NOTE : EACH ALLIANCE MEMBER CAN SEND ONE REINFORCEMENT MARCH ONLY
this trick helps during ke in which our 78mill alliance took out 89 mill outlander
these outlanders attacked our hive and took about 15 heroes all executable we kept thinking what can we do and since our strongest member shielded we needed to do something else.
so my leader suggested that I activate anti-scout, drop my shield, activate my VIP, reset hero skills to combat and other alliance members all would send reinforcements to my city.
then i kept scouting and swearing at the outlander until he sent a march of 350k troops mostly t3 at me and we killed almost 250k troops and lost 40k of the reinforcing troops. All died cuz reinforcing troops cant be sent to the hospital.
Then before his march returned to his city, we rallied him with 90 k t3 and rescued our heroes
u can find me in kingdom#110 my name is Mansafzalama
Another trick alliances can use to help protect troops is to have one city activate a Peace Shield, and then have other cities send their troops there as reinforcements. The troops will be protected for the time of the Peace Shield. This way, each city doesn't have to individually activate a Peace Shield. Note: you cannot protect your Hero by sending him to a shielded city (you can't include a here in a reinforcement march) so this trick works best for cities with heroes that are below level 15 and cannot be executed.