The Sap Sac is a plant native to Tallon IV and only appears in Metroid Prime. Sap Sacs are irresistibly sweet and produce an attractive odor, which nearly saw the plant eaten to extinction. It evolved, however, to produce a chemical that explodes when the plant is disturbed.
Sap Sacs are stationary and do not attack Samus, but if she stands too close when firing upon them, the resulting chemical explosion will cause damage. This explosion is powerful enough to destroy any Bloodflowers in the immediate vicinity. They serve as containers for Energy Units and Missile Ammunition. There is an aquatic version of this plant known as the Aqua Sac.
- "Chemical reaction within sac produces violent explosion when agitated. Because of its irresistible odor and sweet nectar, the Sap Sac was nearly eaten out of existence. The evolution of an explosive chemical sac saved it; now only brave or ingenious creatures dare to devour it." — Logbook "Sap Sac" (Metroid Prime)