He is essentially regarded as the source of the Three Pure Nobles' power, including supplying them with powerful cards in the form of monoliths send through time and space, which included the "Meklord" cards with the addition of Yusei's "Shooting Star Dragon"
Across all of my testing with the theme, there are three standout rules to follow for the rest of the deckbuild that gives the Chaos Ritual strategy all it needs to thrive: Every build needs to have at least: 1 non-theme way to get Skull Archfiend of Chaos to the GY without requiring the Normal Summon 1 non-theme way to get 8 Levels of monster(s) to the GY, to banish for your first Ritual Summon, without requiring the Normal Summon 2+ ways to field a Level 7+ Main Deck monster, that doesnt mind being left on board, that you would also like returned to hand
This desire to help humans survive is reflected in his design
Hes freaking huge , with 3500 ATK serving as a nice surprise to an opponent thinking they can win via battle
Effect canceling - Cards such as "Skill Drain", "Chivalry" or "Effect Veiler" can prevent your monsters from tagging out or negate the effects of the ones that are Summoned, leaving them defenseless against high ATK monsters