//TLDR//
Reenforce other castles with Infantry & Cavalry to protect them from the vikings. Leave your archers and 3 strongest heros at home, send ALL your other troops away. Viking Wave 10 & Wave 20, reenforce the HQ. Pull pack troops from 1 or 2 castles, and send Infantry to the HQ with your 3 strongest heros. After Wave 10, recall the troops from the HQ and send them back to the castles you pulled them from. Shields DO NOT work.
Some suggestions
- For the HQ reenforcement, Archers give you ZERO points. Cavelry about .25 kills per troops. Infantry is close to 1 kill per troop. USE INFANTRY!