How do i beat chaos chimera?

[Caper the Fox]

I won't lie to anyone but this is a hard boss

After failing to beat him at level 40 i spend so much time grinding till level 60 then i tried to see if i can beat him again... But no i still can't win against him even at level 60. So after failing to beat him i felt like i wasted so much time grinding all for nothing.... i tried putting all my djinn's on standby but can't beat him still. and the biggest con about putting them all on standby he uses so much powerful attacks that will KOE'd almost all of my enemies at once faster than when their not on standby and It feels like he has 100000000 million hp because no matter how many times i summon it still does not deplete all his health and you know summon attacks deal alot of damage. Will it take all day to get his health all gone? (this would be the first boss of any game i played that would take that long to get rid of his health if it does take that long)

It don't even matter that i got plenty of recovery items because chaos chimera never gives me the chance to use them all because of the many times he attacks all at once.

So if anyone knows what level is recommended to beat him, Please let me know that way I know I won't be grinding for nothing again =/

[Star Magician]

It's been a while since I beat him, but... I was like level 50 the first time.

First things first, how many djinn do you have? In order for your characters to properly defend against his attacks, you want to have at least 4 set to any given character. This allows you access to classes with better psynergy, in particular, Wish/Healing Gust, Revive, and Impact/Weapon Grace. Protect and Resist are also helpful, but not by much because some attacks ignore defenses I think.
Always have at least one party member who has Revive, preferably Matthew. In fact, his djinn should always be set, not standby, so you can use him to attack more proficiently as well. Use Impact/Weapon Grace on him to boost his attack more.
Also have a healer who can heal the entire party in one turn. If your chosen healer is slow, use the healing spell before your health gets below half because you want to keep your HP up as high as possible. CC will attack, then your healer will heal afterwards. If your healer is faster, heal the party after their HP drops below half instead.
Keeping djinn set on your healer will increase the amount you heal per cast if the healing spell is the same element as that character's djinn. This is far more effective than healing items.
CC will use an attack that drains your djinn, putting them in recovery. This is where it gets tricky. When that happens, I recommend switching out your weakest non-healing party member to a character that has a djinn that can use a defensive wall (Chasm, Shell). This gives you a free turn to recover djinn while taking little damage. If that character also has a djinn that can speed up djinn recovery or block an enemies movement once, use those too. Once you're back to 4 set djinn, summon anything you have, and you can continue attacking and healing. If your attacker can hit several hundreds of damage per turn, it shouldn't take too long.

I was able to beat him on my first try like this.