Thiagosc777
Member
The Adamantortoise (14 million HP).
You essentially need an Elixir to survive it's strongest attack once in order to take it down.
You also need to exploit the Commando Death Spell Trick to do 999,999 Damage at Max Level.
Without the elixir it isn't possible to beat it as the attack is followed by another without a means to heal and you have no time to use your Healing Spells which is why the Elixir is needed in the game.
There is a guide online I followed which recommends this method to beat the hardest enemy in the entire game.
The other 3 are beatable without the Elixir as they have less HP and less resisitances.
The only other enemy that is very difficult and is based on Luck mostly is Gigancatctuar as you need a random instant stagger to beat it within 30 seconds as 10,000 Needles can two hit KO you.
I got 100% on this game and even killed the Long Gui that appears after. I did it without any Elixir.
I'd recommend doing it after finishing the game. For the Long Gui I used a summon (everytime you summon, the monster falls down).