Since Dante and Vergil are of half demon and half human heritage, they have the ability to temporarily transform into another physical form where their strength and speed are enhanced. In the Japanese version of the Devil May Cry games this is called "Majin Mode", and in the English releases it's called "Devil Trigger".

Vergil had achieved his Devil Trigger much earlier than Dante had. Knowing that, it might had been one of the reasons why he had left his brother as he was "lost to evil". During the three fights in the Temen-ni-Gru Vergil does not show his brother his Devil Trigger until the last two fights, which by that time Dante had also reached his own Devil Trigger. Something interesting is that during their first fight it was as if Vergil was trying to push Dante into reaching his Devil Trigger. The reason being is because after Vergil got Dante's half of the amulet, he proceeded to stab his brother while he was still down. Being of half demon, Vergil would very well know that a mere stab in the abdomen will not kill Dante. It seemed as if as if Vergil was trying to put Dante to the point that he would be in so much stress and danger that his body would instinctively activate Devil Trigger on its own. Vergil does succeed in doing so, and seemed almost pleased in a sarcastic way, after Dante rushes at him after flickering a Devil Trigger.

The only game in the series which Vergil's Devil Trigger is seen is in Devil May Cry 3. The design of his and Dante's devil forms was created by Kazuma Kaneko of Atlus. It had caused some concerns among fans in regards to the designs being 'too different' for the game. In general, the key aspects of Dante and Vergil's normal appearance is carried onto their Devil Triggers as Dante is a red devil, and Vergil is a blue devil. Overall, Vergil's physical appearance as a devil changes according to whatever equipment is being used. For instance, when equipped with Yamato, the sword will appear on his left arm, and his wings would seem to form a coat around him. With Beowulf, the only weapon seen would be the gauntlet and greaves, but the wings would be in a different position.

Devil Trigger seems reminiscent to one of the action elements of Akira Toriyama's Dragon Ball series. In Dragon Ball Z and later story lines, chracters who are of Saiyan decent, whether they by direct or half, have a chance of reaching something called a Super Saiyan where their speed and strength are enhanced for a period of time. There are many levels a Saiyan can achieve. If Dante mysteriously gets another level of Devil Trigger, we now all know where the concept may be based on if not already mentioned in an interview....

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