The Shape Japer is after things that come in eights - Four goes on the mission.
Numberjacks: 2, 3, 4, 5, 6, 8
Meanie: The Shape Japer
Agents: 16, 42, 68, 101
Trivia
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Zero, One, Seven, and Nine are absent in this episode.
This episode marks Eight's first appearance of the series.
The Shape Japer stays as a cube in this episode, due to having eight corners.