Thorn-shooter

The Thorn-shooter is basically a weed version of the Peashooter, except it can pop balloons. Before obtaining it, normal peashooter must be used on the Cesspit levels. This is bad, as Peashooters shoot twice as slow.

Use them as you would Peashooters, but on the Cesspit levels. That's all there is to it. Infact, they are a better alternative to Peashooters on normal levels, as they pop balloons.

Almanac Entry
Thorn-shooter shoots thorns at zombies.

Thorn-shooter has always fought for thorns, but fighting for thorns fills Thorn-shooter up, meaning he can't fight for thorns because he is filled up with thorns. Say that 10 times fast.