Card Trivia:Sinister Serpent
- This monster appears in the artworks of "Goblin Circus", "One by One", "Snake Whistle", and "Waking the Dragon".
- This card appears in the artwork of "Exchange" (first Japanese artwork) and "Hand Configuration".
- This monster is based on the Tsuchinoko, a Japanese cryptid taking the form of a snake whose middle body is winder than its head or tail.
- This is one of several Forbidden cards to go through an errata change to balance them out. This card's original effect simply returned it from the Graveyard to the hand for free during the Standby Phase, whereas its errata'd effect adds a cost to banish a copy of this card from the Graveyard during the End Phase of the opponent's turn.