Card Trivia:Submarine Frog
- This card's OCG name, "Unknown Frog"「みちガエル（michigaeru)」is a pun on the Japanese term which means "to be hardly recognized", reflecting this card's appearance as a cartoonish, anthropomorphic frog in contrast with the realistic design of the other "Frog" monsters.
- This card's TCG name is a reference to this monster's design, as it features underwater gear.
- Likely, this monster's appearance is based on the term "frogman," a person equipped to work underwater, which is also a term associated with combat divers.
- This, and this monster's underwater suit also features the letter "F", referencing this card's status as a "Frog" monster.
- This card's TCG name is a reference to this monster's design, as it features underwater gear.
- This is the first TCG-exclusive card to feature a Common rarity.
