Elder Berries

Elder berry bushes are 3.5 blocks tall, found near water and can be harvested for 2-7 elder berries which can be brewed into a potion of purity making you resistant to all effects including good ones, so if your fighting a foe who uses harmful effects as its main offense then this would be very useful, it can also be eaten to shorten bad effects by 3 seconds and can be turned into tea which gives regeneration for 5 seconds made with 6 elder berries and a water bottle