I just can't defeat him! Help! I never manage to get him down to less than 90% health before he defeats me!

This is my current party:
Spot one: https://www.sylestia.com/view/pets/?petid=3764699
Spot two: https://www.sylestia.com/view/pets/?petid=3764654
Spot three: https://www.sylestia.com/view/pets/?petid=3770688

This is a puzzle boss. There is a large message at the beginning of the Forgotten Tomb that you need to decrypt. It'll also make decrypting the smaller message at each seal easy. You basically have to knock 4 buffs off the boss to make him a manageable fight. If you don't knock any of the buffs off, he'll be flat-out impossible to beat.

Sorry, I didn't see your post since you didn't ping me.

I decoded it, but even if I use the right pet for the seal they won't activate. Why? Who should I use for each seal? Should I train up a new pet in a different stat?

The first thing I'd recommend is making sure your pets have gear that matches their elemental attunement. What I see now is random equipment on each pet. There should be guides on this site on how to gear a pet. Assassin gear is best for earth pets, and for your other two pets, evoker gear would be best at this stage.

I think your pet needs to have at least 250 points in the correct stat to activate a seal. Here's how I did it:

*Puzzle spoilers follow:*













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Alacrity: This is speed, so pick the pet that has the highest agility amongst your pets.
Courage: I thought this is for the hero, so I had my character (not pet) use this one.
Cunning: This is about being clever, so it's intelligence.
Perception: To use this skill effectively, you need to be clever, so it's intelligence again.

I think that covers it for the four seals. You'll know you've done it correctly if the fourth seal you come across lights up. By then, you're ready to take on the boss, who will be all alone and all unbuffed.

All right, thanks! I'll try to get some matching gear on them!