Never mind found my answer.

"Marauder: Deserving of a special category of its own, the Marauder trades the defensive power of the Warrior for extremely powerful burst from cross-class cooldowns (all while retaining the fantastic Mythril Tempest). Knowing when to use this burst is key, and it is important to survey the battlefield and note the status of the opposing healers - if they are not disabled or preoccupied, they may counter this burst."