The Mirage Force is for the Sura class. It is mostly a PvM force, where as the Black Magic force is the PvP force for Sura's. They have 6 skills;
Aura of Sword - Enchant the Sword with evil power, Increase Attack Power.
Aphonic - Summons dark energies around you, creating a shield that absords a set amount of damage
Dark Twister - Calls tornados using dark power, dealing massaive damage to nearby enemies.
Fear - strikes fear into your enemy causing it to be unable to use abilities temperate
Rupture - A wave of fire that ripples out from Sura's inverse, causing damage all around him.
Remove Magic - Casts a powerful anti-magic buff at a target enemy unit. Remove their beneficial buffs.
A Mirage is the best PvM force there is, but is also considered one of the the worse PvP force. They have the most even skills. Their skills are the most useful for PvM, Aphonic gives AC which is defence and reflects damage which is attack. While Aura of Sword gives AP wich is attack and a maximum of 15% damage absorbed to hp which is defence that can regenerate their Hp. Fear decreases the damage thet u receive by physical attacks, gives miss chance and lets players not be attacked by agressive Mobs that are lower level than your character (besides boss mobs and Mobs that are directly spawn from metins), also gives chance to weaken the oppenet's ability temporary beside poison. Fear is mostly count as defence which is a very useful shield. While Dark Twister attacks all mobs and enermies around you pushing them back (only when they are charging to the Sura but mosly makes enemies fall down and gives time to use pots and regenerate Hp) and dealing massive damage. Rupture attacks all opponents infront of you and ignore dodge doing very massive damage to enemies. Lastly, Remove Magic is known for PvP that can remove any benificial buffs from players, but some players use it to Lure Mobs. This skill is a defensive skill because it can remove players who has buffs which makes them weaker, it mostly works on warriors or assasins and usually doesn't work on Suras. Therefore, Mirage Suras' skills are the most useful for PvM and are both defensive and aggresive. All their skills can be imprved by increasing INT.