- "These tadpoles often accompany frog Noise. If they latch on, they'll slow you down."
- — Noise Report
Bigbansprog are dark blue sprog Noise with yellow eyes in The World Ends with You that only spawn in the bottom-screen, and only alongside Bigbanfrog. They are the first sprog Noise encountered in the game.
Bigbansprog has no passive capabilities.
- Swarm: The Bigbansprog's eyes turn red and it jumps at Neku, attaching itself to him upon contact. While Neku has any Bigbansprog latched onto him, his movement is limited, losing the ability to dash along with reduced movement speed.
The Bigbansprog's "Swarm" attack, while not particularly damaging, will drastically reduce Neku's mobility. This can easily leave the player more vulnerable to the attacks of other Noise. Fortunately, sprog Noise have low health, so erasing them shouldn't prove too difficult, especially if a psych that affects a large area (such as Pyrokinesis) is used. Alternatively, erasing the "parent" Bigbanfrog will erase the eight Bigbansprogs that spawned with it.
The Bigbansprog's name is a play on "big band" (a type of musical ensemble) and "sprog". "Sprog" is a UK English term for a child, and was likely chosen for its similarity to the word "frog" and since tadpoles (which sprog Noise are based on) are young amphibians.