Level 7 Normal Boss : A yasha coming out of the sea, who possesses the ability to cause tidal waves
LVL 7 boss is the Yasha. He has a 3.4M power and is classified as a medium monster. He will use 20 stamina for an attack. It is suggested by Evony that you can beat these bosses with 80,000 T10 cavalry troops (100,000 T10 for no wounded). I did come across another reference that indicates you only need 27,000 T9, so I would be very interested if someone could clarify which is true for me. The rewards include the level 7 boss chest (contains medals, general exp, material chest and a speed-ups), refining stones, spiritual beast exp, artwork fragment chest and a rare (LVL 3) treasure map. The added bonus to everyone in an alliance is that they will all receive a Medium Alliance Boss package every time a Yasha is killed by an alliance member, (and just to remind you of the contents - which contains 10K food, stone and lumber; training and healing speed ups and a material chest).