Both versions operate identically in combat, bearing a built-in underslung melta gun (in truth, it is modeled in the position that a dreadnought would usually bear a storm bolter or heavy flamer, while in the game it functions closer to a Multi-Melta) with a total of 56% improved reload time over the standard melta gun and a range extended from 21 to 25 meters, and a spread of 12 degrees. It also has an increase in damage from 225 up to 400 for a direct blast.
A Dreadnought may use the Close Combat Weapon to execute a 2 hit combo melee attack, in a narrow front arc. The first hit does 350 damage (250 armor + 100 normal) and the second does 375 (250 armor + 125 normal) which are sufficient to kill almost any class in a single hit. The close combat weapon can also be used during a sprint to perform a charge attack, which will cause 200 normal damage to someone hit directly.
In addition to the melee attacks, the Dreadnought can also perform a 2 hit 'stun combo' attack, consisting of a foot stomp, and then a punch to the ground with its power fist. The first hit of the stun combo (foot stomp) does 300 damage (250 armor + 50 normal damage) and will cause a massive shock wave 8 meters in radius. Enemies close to the epicenter can be pushed several meters back to the boundaries of the shockwave. This stomp will instantly deplete the armor of any class that is hit, but because the attack only does 50 normal damage, any class can survive this hit if they did not have previous health damage. The second hit (power fist to the ground) causes a blast with a radius of 10 meters, and a direct hit will kill any class instantly, regardless of their loadout or condition.