Use the effect of "Armageddon Knight" to easily get a DARK monster in the Graveyard for this card's Summoning.
"Infinite Cards" can increase the amount of damage inflicted by this card's effect, particularly since it also removes the hand-size limit of your opponent as well; more cards to discard means more damage is inflicted.
This card can also serve as back-up for your "Slifer the Sky Dragon". If "Slifer" were to be destroyed and you still have extra cards in your hand, you can Special Summon this card and possibly inflict massive damage.
After using this card's effect, Special Summon the Dragon Rulers from your Graveyard, banishing an "Eclipse Wyvern" to do so. When you banish it, use its effect to add your banished "Victory Dragon" to your hand. Tribute Summon "Victory Dragon" with three of your monsters, and attack directly, winning you the Match.
You can also Special Summon "Keeper of the Shrine" when this card sends itself to the Graveyard. Due to its first effect, it will count as 2 of the required Tributes for "Victory Dragon", giving you three Dragon Rulers to spare. This is especially handy if your opponent still has a large chunk of LP left.
As an alternative, you can activate "Last Will" while you control this card and "Black Metal Dragon", before using this card's effect. When this card and "Black Metal Dragon" are sent to the Graveyard, use "Last Will's" effect to search "The Black Stone of Legend", and "Black Metal Dragon's" effect to search "Red-Eyes Darkness Dragon". Use "The Black Stone's" effect to Special Summon "Red-Eyes B. Dragon", Tribute it to Special Summon "Red-Eyes Darkness Dragon", and attack directly for an OTK.
This card's Nuke effect is a good way to counter the "Timelords", since it sends them to the Graveyard instead of destroying them outright.
Activate this card's effect, then chain "Ring of Destruction" and target "Chaos Emperor Dragon - Envoy of the End" for an extra 3000 damage. However, this will set you back 4000 LP with the combined effects, so it's best to use this strategy if it will reduce your opponent's Life Points to zero so you don't leave yourself open to a direct attack.
Use this card's effect while "Night Assailant" is in-hand to guarantee having a monster in the following turn. "Spear Cretin" is a good candidate.