I was thinking about a game in which Alucard sees Soma as such a theat that he has to be destroyed.
Basically, another cult would be after Soma and he will go after them. Alucard would track down Soma and after soma beats the cult, instead of the game ending there would be one final boss: Alucard. he would say that soma is too reckless and is putting the future of mankind in a dangerous situation. Thus he must be destroyed. Half way through the battle Alucard, who is in his disguised form of Arikado, would reveal his true self to soma and attack at full power. It is at this point in which there would be one of two endings. the winner of the fight would loss his humanity and become the next dark lord. Then there would be two Julius modes. in one, the final boss would be Soma and in the other Alucard would be the final boss. And of course the bosses in each Julius mode would differ depending on which one is the final boss.