With access to powerful weapons such as the Heavy Bolter, Lascannon and Plasma Cannon, Havocs wield amazing firepower. They are most often found holding key positions with good fields of fire, allowing them to bring their weapons to bear from long range. Overwhelming firepower is what they offer at the expense of maneuverability.
In multiplayer the Havocs are fearsome when engaged in a ranged firefight. They can lock down sections of the map with their firepower, regardless of what weapon they wield. Each of their weapons offers its own powerful alternate fire mode, such as the Plasma Cannon's charged shot with a blast radius, the Heavy Bolter's braced stance with an increased rate of fire, or the Lascannon's powerful and accurate charged shot.
Devastators suffer a huge mobility disadvantage compared with tactical marines. They lose the ability to roll through opponents, instead gaining a 6 meter 'hop'. While their walk speed, and speed while aiming remain unchanged, they only can move up to 115% speed while running. Their melee damage is a poor 30 damage kick, but the stunning stomp attack and defensive perks improves Devastator survivability enormously. Also of note, just by standing next to it, there is a glitch that allows the Havoc to shoot through some cover, although this does not work with the Plasma Cannon (both fire modes).