Combat is the main gameplay aspect of Izanagi Online. Almost all the PvE quests in the game involves some form of fighting: defeating normal monsters, scavenging for items dropped by said monsters, defeating bosses, war quest, etc. As is true for most MMOs, Izanagi Online also gives players the option to follow the "holy trinity" design, where all classes fall into either of three designated roles: tank, damage, healing. In addition to that, however, Izanagi Online allows daring players to pursue unconventional class abilities through the second-class system. For example: Warriors who do not want to be limited to the traditional tanking-role can upgrade to Gladiator, a more damage-oriented class; Clerics who do not want to be limited to a pure healing role can opt out into a more tanky/damage-dealing role with the Crusader class. Due to a diverse skill and stat system, all classes have the potential to contribute to combat in multiple ways. Every class has the potential to deal sufficient damage and every class has the potential to survive in fights.
With proper understanding and usage of tools such as the unique Special Skill, the jump function, the rotating skill wheel, skill combinations, and timing, all classes can contribute in combat a lot more efficiently.