well unlike in a DH army you should never rely on a dreadnaught that much. true they are good and quite powerful and should be able to climb buildings as they move like infantry.
what ive done before is get 3 dreads and give them assault cannon and dread combat weapon and march them down one side of the table and sweep up through the enemy while 2 deepstriking grey knight squads drop on the other end and a grand master and his termies and land raider go straight up the middle.
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