Use Beginning and Evening Twilight Knight to ritual summon a Black Luster monster and then you can special summon monsters by banishing them which allows you to get a ritual monster and spell of your choice, such as Blue-Eyes Chaos MAX Dragon which inflicts double piercing damage to defensive monsters. When you have 2 level 8 monsters on the field you can XYZ summon Number 38: Hope Harbinger Dragon Titanic Galaxy whose effect can add XYZ materials by deactivating any spell or effects and adding that card, making it perfect for ritual, equip, or any other deck that requires or is supported by spell cards.
Just fill in the rest of the extra deck with XYZ monsters of your choice, enjoy.
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