Activate Dark Contract with the Gate, add D/D Swirl Slime or D/D Lamia (whichever you don’t have) from the Deck to the hand.
Activate D/D Swirl Slime’s effect, Fusion Summon D/D/D Flame King Genghis using D/D Swirl Slime + D/D Lamia.
Activate D/D Lamia’s effect, send Dark Contract with the Gate from the field to the GY, Special Summon itself from the GY.
Activate D/D/D Flame King Genghis’ effect, Special Summon D/D Swirl Slime from the GY.
Link Summon Crystron Needlefiber using D/D Lamia + D/D/D Flame King Genghis.
Activate Crystron Needlefiber’s effect, Special Summon D/D Lamia from the Deck.
Link Summon D/D/D Abyss King Gilgamesh using D/D Lamia + D/D Swirl Slime.
Activate D/D/D Abyss King Gilgamesh’s effect, place D/D/D Oblivion King Abyss Ragnarok + D/D/D Chaos King Apocalypse on the Pendulum Zones, take 1000 damage.
Activate D/D/D Chaos King Apocalypse’s effect, banish D/D Swirl Slime + D/D/D Flame King Genghis from the GY, Special Summon itself.
Activate D/D/D Oblivion King Abyss Ragnarok’s effect, Special Summon D/D Lamia from the GY, take 1000 damage.
Synchro Summon D/D/D Cursed King Siegfried using D/D Lamia + D/D/D Chaos King Apocalypse.
During the opponent’s turn, activate Crystron Needlefiber’s effect, Special Summon Formula Synchron.
Activate Formula Synchron’s effect, draw 1 card.
Activate Formula Synchron’s effect, Synchro Summon D/D/D Gust High King Alexander using Formula Synchron + D/D/D Cursed King Siegfried.
Activate D/D/D Oblivion King Abyss Ragnarok’s effect, Special Summon D/D/D Cursed King Siegfried from the GY, take 1000 damage.