Minecraft wiki entry for Damage, associated text: Cave spiders, witches and bees poison players when they attack (except on easy difficulty). Pufferfish inflict poison as defense against players or certain mobs if they are nearby. Poisoning also occurs upon eating a spider eye, poisonous potato, pufferfish, or suspicious stew made out of lily of the valley. Drinking or being hit by a potion or arrow of poison also results in poisoning. While poisoned, the hearts in the health meter turn from × 10 ( × 10 on Hardcore) to an olive green ( × 10)( × 10 on Hardcore) and the player takes 1 every 25 ticks (1.25 seconds) on level I. See Poison for a table for higher levels. The Poison itself cannot kill the player, but it can reduce them to half a heart (), thus leaving them vulnerable to damage from other sources.