There are two sets of monsters, neutral and aggressive.
* Neutral monsters are monsters that do not attack unless the player attacks first.
* Aggressive monsters attack if the players are within their proximity. Exceptions is if the player is 15 levels or higher than the monsters. Exceptions may be certain boss character that still attack on any level, need confirmation on this.
Another setup is where monsters attack in groups.
* Trap monster are monsters that when attacked triggers a group of monsters to attack the player at the same time.
* Retreat method is where the monster retreats to a location and triggers help to other similar monsters within the proximity. This method does not always yield other monsters to attack.
Types of monsters are as following.
* Monsters, the normal easy to kill monsters.
* Elites, are monsters that are stronger and has more HP.
* Cyclic, are normal/elite monsters that only appear at certain time of day or night.
* Nightmare, are monsters that only appear at game time, 23:00 - 02:00. These monsters are harder to defeat.
* Boss, are tough monsters that when defeated, usually drops better items.
* Raid Boss, are very tough monsters that usually require an alliance group to defeat it.