I know some of you are still anxious for KHBBS hacked fights, but please be patient, it'll be a few weeks while I start making them. In the meantime, enjoy these.
Tantarian is an optional boss that can only be fought on Disc 2 or Disc 3 at very specific parts. However, it is ideal to fight him on Disc 3 instead of Disc 2. Reasons being, he's much easier on Disc 3, you don't have a time limit like you do on Disc 2 (so you can steal all his items), and you'll have better equipment with better Abilities so you can make full use of the AP you win in this fight.
He can be found in Alexandria Castle in the Library. There is a book on top of a shelf. Speak to it and it will let you challenge it.
Plot
There is no plot for this boss.
Strategy
Unfortunately you have a slight difference in parties depending on when you take on this boss. If you do it on Disc 2, you have Steiner instead of Amarant. I will be writing this if you're taking him on in Disc 3, as that's the best time to fight him.
Alright, so with a proper set up, you can make it so you will take practically no damage in this fight. With the wrong setup, the boss will tear you to shreds, annoyingly. Before going into the fight, make sure everyone is equipped with Antibody. The boss constantly casts a Poison spell at certain points, so that's a bunch of turns you don't want to waste curing yourselves. Super easy ability to get, everyone should have had it since Disc 1 (Except Amarant).
On Disc 2 you should have everyone in the Back Row, on Disc 3 it's up to you. Here is how the boss works: When you attack it, it opens up to a page. If the page is 150-200, the boss' true form emerges, where you can deal the most damage. Knowing how to get the book to open to those pages is what makes this fight easy. For the first hit, the page opens on the page equivalent to your damage. For example, if you attack it and it does 50 damage, it opens to page 50. However, after that the damage you do gets added to the page. So if your next hit does another 50, it'll open to page 100. Knowing this, you should be able to get the bosses true form to emerge quite easily.
Do note that the boss has crazy defense when the book is shut. Your physicals will do very little, especially if you're in the Back Row. Even magic is limited damage, but is better. Also, make sure you do not queue up a bunch of attacks. When the boss emerges, it shuts the book after 1 physical attack. And you don't want that one physical attack to be weak. Instead, try to do it one at a time if you can.
For the bosses main attacks, he has Paper Storm, the most deadly. It deals a ton of damage to everyone. The boss is not afraid to use this multiple times in a row. Edge deals tons of damage to one character, and Doom will kill you after the counter hits 0. As for a tip on Doom, if you have ATB set to Wait in the Config menu, you can abuse slowing down the counter by keeping a menu open which stops the counter during animations. People sometimes frown upon this, so it's up to you if you want to do that.
When the boss' true form is present, he only uses Poison....Yup. However, you're going to want to make full use of this. DO NOT attack him physically during this or you'll have to open it up again. Instead, have Vivi spam cast Fira. It's weak to Fire, and it won't shut itself if you hit it with magic. Repeat opening and Fira'ing him 5-8 times and you'll end this, as the boss has 20k HP.
Now I will explain how to set this up so you can pretty much never die. First, put everyone in Back Row. Next, have Freya cast Rei's Wind and keep it up when it runs out. Next, get the book open. With a Fira from Vivi, it should open in 2 rounds. Now that the book is open and the boss will only be using Poison, you are free to do whatever with everyone as Vivi is spamming Fira. One thought comes to mind: What about MP? The answer: Chakra. It's Amarant's ability, and it restores HP/MP to the player you use it on. Use it on Vivi at least two times during this phase. Then use it on Freya who has been using Reis' Wind, and then on Amarant himself probably once to restore his own MP (Chakra uses 4 MP). There is an ability to have Chakra restore more, so if you have it, equip it.
With the above setup, you'll be fully restored on HP & MP WITHOUT ITEMS during the bosses true form. Use this to have Zidane spam Steal infinitely until you steal all the items. However, just as a note, Demon Mail is its hardest steal, and it's a 1/256 chance each time. Bandit ability slightly increases it, but not by much. You could be stealing for over an hour and not get it, and the equipment itself is not really that amazing, it's just a good Defense boost for this point in the game. You can buy it fairly soon anyway, so if you don't want to steal it, don't. But steal the other items at least, they're not too hard.
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