Tangle Weed does not have the strength to hold down large organisms, making it harmless to Samus. It does, however, slow Samus's movements down considerably if she walks over them by injecting paralyzing toxins from its thousands of barbs. If Samus attacks the plants with any weapon, Tangle Weeds will retract into the ground and remain there for a moment. Because of this cautious nature, Tangle Weeds cannot be destroyed by Samus. Tangle Weeds seem to be a common species considering they appear in many worlds. They adapt to their local environment, keeping distinct characteristics but the same basic behavior. These plants are related to the Venom Weed, a similar plant with damaging toxic characteristics as well as paralyzing toxic abilities.
Samus first encountered Tangle Weed patches throughout Tallon Overworld and Chozo Ruins in Tallon IV. Tangle Weeds serve more as a nuisance than anything else, considering that they are unable to damage Samus and Samus is unable to destroy them.
Tangle Weeds are also encountered on the planet Phaaze. Due to Phazon radiation, these Tangle Weeds have become much more dangerous. Aside from the ability to slow down Samus, Tangle Weeds on Phaaze damage Samus due to high Phazon levels. They only appear in Drop Shaft, where they become an obstacle along with Metroid Hoppers and Phazon Hoppers, trying to keep Samus from destroying red Phazon crystals in the center of the shaft. After destroying the red Phazon crystals, all creatures in the room are destroyed, including the evasive Tangle Weeds.
- Though the Corruption Logbook entry states that the plant will sway its "brightly colored leaves" to attract other creatures, the Tallon IV species of this plant has a very dull, brown color.
- Even though they are able to damage Samus in Corruption, they are still classified as Tangle Weeds and not Venom Weeds.
- "A simple form of plant life of which there are many species across many worlds. While each breed may have characteristics native to their respective ecology, they all possess identical behavior. Tangle Weeds constantly sway their brightly colored leaves to attract potential prey to land on them. The thousands of microscopic barbs lining the Tangle Weed's body will snare and inject a paralyzing toxin into their victim. While small organisms are unable to escape, Tangle Weeds lack the strength to do anything more than hinder the movement of larger life-forms. When attacked, they will retract into the ground until they no longer sense a threat." —Metroid Prime 3: Corruption Logbook "Tangle Weed" (Metroid Prime 3: Corruption)
- "Plant life with basic sentience. Retracts into ground if threatened. Tangle Weeds are only dangerous to small organisms. They are covered in tiny barbs designed to trap potential meals. Tangle Weeds lack the strength to do anything more than hinder larger life-forms." —Metroid Prime Logbook "Tangle Weed" (Metroid Prime)