Mushroom

The mushroom exists in 5 Zelda games, A Link to the Past, Link's Awakening, Ocarina of Time, Oracle of Seasons, and Majora's Mask. In ALttP and LA the mushroom is given to the witch for magic powder. In OoT it's merely a trading item to get some magic powder for a lost man. In OoS, it is an item in the Trading Game, a quest for the L-2 Noble Sword. In MM, it is used to sell to one of the hag sisters for 40 rupees.