"Darklord" monsters have a few things in common: in addition to being DARK Fairy-Type monsters, they all have high Levels (ranging from 5 to 10) and all of them have high ATK to match. Also, some of them, such as "Darklord Superbia", can swarm the field.
A "Darklord" Deck focuses on sending DARK Fairy-Type monsters to the Graveyard and then reviving them; however, bringing back a monster- especially a "Darklord"- requires a more permanent solution rather than relying on one time use cards such as "Monster Reborn", "Call of the Haunted", "Ribbon of Rebirth", etc. It is recommended to run multiple copies of "Athena", "The Dark Creator" or "Sephylon, the Ultimate Timelord". The downside of using the effect of "The Dark Creator" is that a clear field is needed. One can send one "The Dark Creator" to the Graveyard, then summon "Phantom of Chaos" to copy its effect, though this is a solution that cannot be used for more than one turn. "Sephylon" is extremely powerful but requires having at least 10 monsters in the Graveyard to summon him. For these reasons, "Athena" is the most reliable and best option. "Athena" also works well with "Darklord Zerato", whose effect would cause it to destroy itself at the end of turn. Using the effect of "Athena" you can send "Zerato" to the Graveyard and then revive it, thus resetting "Zerato" and preventing it from being destroyed.
In order to perform this OTK you need to have plenty of DARK attribute monsters in your Graveyard plus one "Athena".
How to do it:
Play "Valhalla, Hall of the Fallen" and then Special Summon "Darklord Asmodeus". Use "Asmodeus'" effect to fill your Graveyard with DARK Fairy-type Monsters. Eventually your opponent will have to get rid of him to prevent him/her from the monster's 3000 ATK Points threat. When the opponent does, once again use "Valhalla's" effect so as to Special Summon "Athena" or you can Special Summon "The Dark Creator", then Special Summon "Darklord Superbia" and use "Superbia's" effect to Special Summon "Athena". Afterward, either Summon a Fairy-type monster or send "Darklord Superbia" to the Graveyard in order to Special Summon another "Darklord Superbia" and use her effect to Special Summon another Darklord such as "Darklord Zerato". Use "Zerato's" effect to clear the field and then head for a Direct Attack, performing an OTK.
This Deck's main objective is the mill and special summon of "Darklord" monsters with the aid of "Lightsworns". This deck uses "Athena", "Darklord Superbia", "Darklord Zerato" and "Lightsworn" cards to quickly gain field advantage over your opponent, and then destroy all of your opponent’s monsters using the effect of "Darklord Zerato" in order to deal mass amounts of "life Point" Damage to your opponent. This deck also has an abundance of draw and search power to speed up the deck. Utilizing the high amount level 8 monsters this deck uses, you can use cards such as "Trade-In" and "Advance Draw" so you can severally thin down your deck.