There's more to worry about than just Cast Times and Cool Downs.

Advantage versus disadvantage is not talked about too much within the realm of MMOs, because of the nature of traditional role-playing game combat systems. However, due to the emergence of TERA as an action MMO with hybrid elements from other genres, this is an important concept to be aware of and put some thought to.

People are used to thinking about moves in terms of just cast times and cool downs. When the cast time is finished, the ability instantly takes effect, and you are back to neutral status where you become free to move and act as you please. When the cool down is over, you are ready to go again. However, when you get into many action systems, there are mechanics and phases of animations, such as startup, active and recovery time, that you should pay attention to.

For example, a move with a cast time of 2.5 seconds may actually take 1 second to start its damage or effect (startup), have that effect last for 0.5 seconds perhaps when hit boxes are allowed to collide and register (active), and the remaining 1 second is when you are stuck in animation (recovery). Without any interference, normally you must wait for the recovery period to finish before you return to neutral. That period is when you are in disadvantage and unable to do anything, while other people are free to punish you with quicker moves, either in anticipation or reaction, provided they are already positioned and in range. On the other hand, if you already have a move about to enter the active phase and your opponent is unable to start in time to interrupt with anything useful, it could be said that you are in advantage.

To minimize this, it’s important to learn about block or move canceling techniques and timing if applicable to your class. Block or move canceling is the act of canceling the animation of another attack, with a block or movement skill. It is commonly used to shave off recovery time, but it's possible to use it during other phases for some actions. Reasons to do this include changing your mind or attempting a bait and punish. Note that if you do it too early, you will cut it off before the activation, but if you do it late enough, the skill actually does take effect and you may gain options to perform a series of actions faster than normal. It may take some time to get a natural feel for using this with all your cancelable skills.

Please keep these things in mind when dealing with skill use, management and timing. It can be applied to increase the effectiveness of your play during any phase of a fight, from engagement to finish.