Vampire Conquistador

Exultation. As long as it is night, the vampire conquistador has a flying speed of 30 feet.

Mark of the Vampire. Whenever the vampire conquistador reduces a creature to 0 hit points, if that creature was affected by the hit point reduction from the vampire conquistador's bite attack, it becomes a vampire in addition to its other races and, if applicable, rises from the dead. It is considered an undead in addition to its other types and has the vampire conquistador's bite attack. If it already has a bite attack, that attack deals an additional 2d6 necrotic damage instead, and reduces the target's hit point maximum the same way. This effect persists until it is dispelled by a greater restoration spell or an equivalent effect.

Sword. Melee Weapon Attack: +5 to hit, reach 15 ft., 1 target. Hit: 1d10 + 2 piercing damage. 

Bite. Melee Weapon Attack: +5 to hit, range 5 ft., 1 target. Hit: 1d6+3 piercing damage plus 2d6 necrotic damage. The target's hit point maximum is reduced by an amount equal to the necrotic damage taken, and the vampire regains hit points equal to that amount. The reduction lasts until the target finishes a long rest. 

Vampire's Zeal. Once per day, the vampire conquistador enters a frenzy of bloodlust. For the next 3 rounds, all of its attacks deal an additional dice of damage, and it can attack twice on each of its turns. However, it must succeed on a DC 14 Wisdom saving throw or indiscriminately attack the nearest creature with blood using its bite attack for the duration.