Reinz had every right to be arrogant, after all, even among the best, he was at the top. In his case, no matter how arrogant he was, it was almost the same as pride.
However, when Reinz said that he would finish the fight quickly and he wouldn't need his Nexus, he was serious.
Those were words he believed in with a full heart. Not only because he thought he was stronger than Adam, but because Reinz was sure that he possessed something that the Phantoms at the Twilight Palace had yet to grasp - the Stellar Resonance.
Every K3-Phantom had The Crystal Gates, as well as five lesser gates. However, the paths to opening the lesser gates could vary greatly, as well as the time required to do so.
The Phantoms at the Twilight Palace had reached K3-Level no more than two months ago, Reinz was no exception to this rule.