Pop Green

Pop Greens (ポップ グリーン, Poppu Gurīn) are the seeds of the hostile plants in the forest of "Greenstone" on Boin Archipelago. They can grow from seeds to full-sized plants in moments.

History
Heracles uses these seeds as bullets and weapons. According to Heracles, they have various uses. Heracles taught Usopp how they work.