Possessing a strong sense of pride, Berkas always wanted to be independent of his species and create his own rule. However, the power structure of the Iron Dragon species has been firmly established for thousands of years, which consisted of the younger dragons being subordinates to the ancient and more powerful dragons, and Berkas soon concluded that it was impossible to gain power in the Underworld. Thus, he decided to rule over Aernas where the flow of mana is unstable and inferior mortals reign. After much preparation, Berkas succeeded in opening a Dimensional Portal to the human world. Leading his army to Aernas, he began constructing his own nest in the deserts of Alcubra.
At some point, Rufus had engaged Berkas in battle alone that ended in the bounty hunter's defeat. It is during this fight that Rufus lost his left arm.
However, his passage was detected by the Holy Knights who were immediately dispatched. Upon locating his lair, the knights quickly constructed magical equipment that would aid them in the battle against this massive creature. Unfortunately, after a tremendous battle, the knights were forced to retreat before they were completely exterminated by the dragon. The Grand Chase who were traversing Alcubra's deserts at the time detected a mana collision and decided to investigate.
Upon their entry into his lair, Berkas detects the opposing forces and, after realizing that Rufus is with the Chase, subsequently mocks him, saying that his prosthetic left arm "remembers [Berkas]" and asks if he wants to lose his right arm as well. The dragon then declares Aernas all of his before the forces clash.
After an incredibly heated battle, with both sides extremely fatigued, Berkas is surprised at how mortals can match his power and is thus forced to retreat, but assures that next time his enemies will kneel before him. Rufus swears he will cross off Berkas' name on his bounty list in the next encounter.
Every attack of Berkas has a warning label and deals high damage.
Berkas stomps the ground with one foot, generating a earthquake which throw in air the players unless they were in air or jumping. This is the only attack that does not damage the Magical Devices.
Berkas roars and summons bursts of fire pillars randomly all over the battlefield. The Catapult Device can interrupt this attack.
Berkas unfurl his wings in order to generate a wind storm around him, knocking players far away. This attack can hit the player two times, if he/she is close enough to Berkas.
Berkas stomps the ground with both his feet to knock up players beneath him before breathing flame forward; this attack will generally instantly kill the player unless he/she counters.
Berkas will use this attack after losing approximately 10% of his HP in one assault under the effect of a Suppressor. Berkas will fly to the left, starting from the lower-right corner, then from the upper-left corner he flies to the right, and lastly, he will breath fire while flying from the upper-right corner to the left. The breath leave flames on all over the map, dealing heavy damage that can kill players. In order to avoid the attack, the player must activate the Barrier Device. Berkas will keep repeating this attack until he is shot down by the Catapult Device.
Berkas swings his tail to hit and knock away any player behind him. This is the only attack that doesn't have a warning label.
There are two common tactics used among the players:
The normal way to defeat Berkas: some players are assigned to protect the Devices from the monsters, other are focused on dealing damage to Berkas. When the Suppressor is ready, all the players will focus their attacks on Berkas. While Berkas is flying for his Aerial Breath, the player who protects the Catapult Device will activate it, knocking him down, making it the perfect time to activate the Suppressor and call an all-out attack. Some players may be assigned to deal with the Hatchlings as well. If someone messes up or something goes wrong, the player at the Barrier can activate it in order to mend the mistakes and gain more time to reorganize.
This is another way to defeat Berkas: one player is assigned to the Barrier, while all the other are assigned to the Suppressor. At the beginning of the battle, the players clear the mobs, wait, activate the Suppressor, and commence a full-scale attack on Berkas. The damage dealt must be enough for make him fly. After he starts flying and breathing, the player assigned to the Barrier will activate it to protect its teammates; and when Berkas is close to the left edge of the map, the players activate the Suppressor early, as Berkas will be exactly over the Suppressor but only for a moment before he flies forward: that is the time for all the player at the Suppressor to unleash every special skill and pet attacks on Berkas while he is flying by. As long as Berkas is not shot down by the Catapult, he will keep flying, regardless of the damage he takes. A typical charater used for this tactic is Mari, because of the Geas/Polaris dual wielding system combination, which is extremely useful as Geas's Freeze Tempest deals insane damage to Berkas,due to his huge hitbox, and Polaris's Sector Lv3 Portal between Barrier and Suppressor shortens the distance and create a safe shortcut to travel between the two Devices.
Advantages over Ground/Land tactic:
- Berkas will have a larger hitbox as he is stretched forward, also he will fly forward, making special skills such as Dragon Spear, Dive Bombing, Raging Fire Blaster, and Stick Lance deal continuous damage.
- The Hatchlings won't heal Berkas, because they can't reach him, as he will be always flying forward.
- The players can totally ignore the Catapult and the Ballistas Devices; they aren't necessary for this tactic.
Disadvantages over Ground/Land tactic:
- Only certain characters and jobs can deal effective damage to Berkas while he is flying.
- When a player does this dungeon by himself/herself, the player should use a job or a character with fast movement (or Mari's Polaris portals), otherwise he could miss the chance to attack Berkas.
- Time is strict: if one messes the timing of the Suppressor or the Barrier, the players will miss the chance to damage properly Berkas or they will burn in the flames left by the Aerial Breath. Also, without the barrier, the flames will mostly like have destroyed the Magical Devices, forcing players to wait until the Devices are functional again.
- Also, monsters could be more troublesome with this tactic than with the former one: for example, they could spawn, push and knock away the player at the barrier right when Berkas is breathing from above; or they could disrupt the players, which had the MP charged in order to attack Berkas, by hitting them, thus making them counter, or making them use their skills earlier in order to prevent being countered.
- Unlike Gorgos or Wyrm Spawn, who are said to be powerful and feared dragons but are easy to defeat, Berkas is the only dragon that truly depicts how fearsome and challenging the dragon species are.
- Berkas' pride and dominance is a typical example of a dragon's often depicted nature, as they are occasionally shown to be prideful and dominant who thinks everyone are below them and possess the extreme desire to rule and conqueror everything.
- Berkas is mentioned to be about on the same level or above than Grim Hand, one of the monsters Ley is able to partially summon.