I was interested in finding this little combo while I was using a Vampire Lord, His effect is that if he's destroyed by a magic, trap, or card effect, it is immediately special summoned onto the owner's side of the field his/her next standby phase, figuring that since tribute to the doomed u have to discard a card to destroy an opponent's monster, discard vampire lord, and same with horn of heaven, Offer one monster to negate a summon, flip summon, and special summon of a monster. Just offer Vampire Lord and u are certain to have a monster on your next standby phase!