Starting from Ainz Ooal Gown, simultaneously traveling through time

Leylin was unlucky enough to be transported to the world of the Undead King by a stroke of luck, but luckily he arrived more than 200 years early, avoiding the direct threat of the Bone King. Unfortunately, he was transported to a country called Inberia, where he'd likely be attacked by a dragon calling itself the "Coffin Dragon King" soon. Fortunately, he was a protagonist in a simultaneous transmigration story, able to share the power of his counterparts from other worlds. Game of Thrones Leylin: "The Unburnt's constitution is immune to fire, but this guy probably doesn't breathe fire. I think you should try taming it?" Lord of the Rings Leylin: "I have some experience slaying dragons, but it's probably not quite the same as Smaug." Dragon Leylin: "[Triple Bloodlust]! [Word of Power: Candle Dragon]! Go and explode it!" Monster Hunter Leylin: "Perfect timing, I've transmigrated into an Ancient Dragon. I'll lend you this Ancient Dragon power and see if it's stronger or I am!" Pokémon Leylin: "Me too!" Digimon Leylin: "This is a standard dragon. Check out [Dragon Beast Slayer]." Type-Moon Leylin: "Add my [Dragon-Specific Attack] too, and the effect will be remarkable." Jobless Leylin: "Front Dragon Gate! Open! Back Dragon Gate! Open! Dragon Saint Aura! Light Greatsword!... What an exhilarating battle! I'll probably never forget you!" Ainz Ooal Gown Leylin: "Thank you, my godfathers! Now... I lack nothing!"