Builders have the advantage of controlling the flow of the map. Knights, especially newer players will just follow the easiest path left or right, making their way to the enemy base. As a builder, take it upon yourself to make the easiest path the best path, make your knights travel to enemy weak points, and cover doors with a wood block (so they can still break it if need be) If it is clearly just weakening your team. Forcing your knights to travel over buildings is forcing them to fight anyone who is bombing the top, rather than going for the more exciting/easier option of just running to the enemy base. Also, enemy knights will break in, but if you make easier to break points in easy to defend positions, they become cheap points of defense. Just some ideas, I am probably worse at builder than anyone who cares enough to read this, so take it with a heaping spoonful of salt.