The Otter Twins are the characters are appear in the game Mighty Math Carnival Countdown[1].
They later appeared in the game Mighty Math Zoo Zillions[2]. They are the pair of river otters named Odd the male and Even the female. They are named after different number descriptions. They each say one line and a half just like the Two-Headed Alien from Putt-Putt Goes to the Moon and Bash and Dash from Thomas & Friends, which will make Ferdinand say, "That's right!".