Card Trivia:D/D/D Doom King Armageddon
- The phrase 死偉王 shiiō ("Great Death Lord") in this card's Japanese name is a pun on "CEO" (Chief Executive Officer), which is pronounced identically in Japanese. In the anime, the signature user of this card, Declan Akaba, is the CEO of Leo Corporation.
- This pun is accounted for in this card's given English name, where the phrase is localized as "Cruel End Overlord".
- This monster is tied with "Mayosenju Daibak" and "Odd-Eyes Rebellion Dragon" for the highest ATK of all Pendulum Monsters.
- This card marks the first time in Yu-Gi-Oh! where the rival's ace monster isn't a dragon type, but instead a Fiend-type
