The second battle between the Vampire King Alucard and the Judas Priest Regenerator Anderson.The fight lasts up until Anderson strikes down Alucard so unfortunately we will not get to see the climax until the fight until OVA 9 (Which let's just hope that doesn't take 2 years to finish.)
While they do not own Hellsing, I feel obligated to give credit to the HellsingCallToArms fan site of which I downloaded the OVA torrent. They have been great at providing us with legitimate Hellsing news and if you have not yet heard of them, I suggest checking out their site.
Upon my personal notes for the battle. It is certainly an epic showdown that showcases the two powers and their ideals battling valiantly against each other. IMO the best part of the battle is Pre-Helena's Nail. It's fast, epic, action packed and filled with all that Norio Wakamoto and Nakata Jouji ham. Although I do wish a little bit more was put into Anderson's counterattack against Alucard's familiars, I am nevertheless happy with what came out.
Post-Helena's nail is a little different. Why it is still an amazing fight, I can't help but think that it was a bit too rushed for my liking. Although the fight itself is rather short in volume 8. Once again though it is still a pretty damn good fight as we finally get to see a fight in which not only does Alucard not completely destroy his opponent but for the first time, Alucard himself must finally be absolutely serious against an opponent of Divine Power.