- This monster is the same as "Great Shogun Shien" and "Tenkabito Shien", as supported by the Master Guide 3 card storylines. But for some unknown reasons, "Legendary Six Samurai - Shi En" is DARK-Attribute while the other 2 monsters are FIRE-Attribute.
- This is the first "Six Samurai" Synchro Monster.
- The "Shi En" instead of "Shien" is explained by the fact that in the Japanese card, the name "Shien" is written only with katakana "シエン" while on cards such as "Great Shogun Shien" or "Tenkabito Shien" it is written with the kanji "紫炎" overcome furigana "シエン".
- "Shien" means "Blue Flame", while the other spelling, "Shi En", can essentially be translated as "Death Flame".
- This monster appears in the artwork of "Six Strike - Triple Impact".
- This monster's armor appears in the artwork of "Shien's Scheme".
- This is the only "Six Samurai" monster to have been Limited, and later Semi-Limited.