As the main ingredient, yes; however you do need Netherwart to make the water bottle into an Awkward Potion. Then just add the spider eye and it will turn into a Potion of Poison.
Fermented Spider Eye+Potion of Fire ResistanceorPotion of Swiftness
There are no instant kill potions in minecraft at the moment, just potion of harming, which can do 3 or 6 hearts of damage.
Use Spider eyesUse Fermented spider eyes on Regeneration potions
with fermented spider eye (spider eye, brown mushroom, and sugar)
Use Spider eyesUse Fermented spider eyes on Regeneration potions
First off, bottle of water and some Nether Wart. That'll get you an Awkward Potion. Most versatile base potion. From there, either a Glistering Melon or a Spider eye. That'll get you a Potion of Healing or Potion of Poison, respectively. Then, add a Fermented Spider Eye. That'll turn either into a Potion of Harming. For the record, Glistering Melons are made with a Melon slice and a Gold Nugget, and Fermented Spider Eyes are made of a Spider Eye, a Mushroom, and some Sugar. Add Glowstone to a Potion of Harming to get a Potion of Harming 2. Redstone to that to change it back. And, Gunpowder to make any potion into a Splash Potion.
brew just a nether wart or a glistering melon
brew just a nether wart or a glistering melon
use the night visio potion with the water botle and there you go.
combine magma cream and the awkward potion
A golden carrot will get you a night potion in Minecraft. I suggest checking the related links for a full list of brewing. Who knows, you might just learn a thing or two! It is very helpful!
you don't there is none