So.. I'm stuck.

I need to have a better team, but I don't know what to do.

My team is currently:

Slot 1: Twilight Lumiance, Shadow, 2 Health (Level 38)

Slot 2: Zodiac, Air, 1 Int/Str + 1 Dex (Level 35)

Slot 3: Heaven's Spirit, Light, 2 Int (Level 38)

I have full Illusionist on Twilight, full Myrmidon on Zodiac, and partial Arcanist on Heaven's Spirit.

What do I do?

I mean, stat-wise they're all pretty respectable? Make sure the equips are good both level and rarity wise (they currently don't have any of their equips on so I can't comment more than that?)

I think? Shadow is a more agi-oriented tank? But. I don't know what I'm doing with a shadow tank so I don't really get to comment. Shadow might also want int, because shadow's entire thing is > deal damage > inflict draining-type debuff on enemy > get healing that is calculated relative to the damage dealt in the original attack

Update

I got all of them leveled to 60, and put some Forsaken gear on them.

I still need to get the second bracer, and profs are the same.

What now?

Forsaken? I'd call lv50 mythical equips that since DotF is the only place you get them? What they have is Exotic Grove equips.
Mm, I'd say go at least partly pyromancer on Heaven's Spirit, since critical hits are pretty useful for a light healer, and go dex prof once she's 65 since she's already 3int. Light healers typically go Dex over Agi, since critical hit = higher damage = higher heal. Lightbringer are more for Light Tanks overall.

What about Zodiac and Twilight?

I didn't mention them because they should be fine (though I can't speak on shadow profs you'd have to ask someone else about those)

Alright.

I mainly made this thread because I was having trouble with Desius. I can't read the inscriptions, and it's really hard to get the right stat!

Also, the order that the seals go in is just random for me!

you can translate the inscriptions fairly easily with observation- it's 1-to-1 letter substitution, and there are guides that just straight up give the answer, too.
The Seals each tell you which stat they want (though they don't use the words "Strength"/"Intelligence"/"Dexterity"/"Agility"

You might want to look at this thread for elaboration on the letter substitution puzzle, and the words the tomb uses for each of the stats

(Zodiac could do the strength one and dex one, Heaven or Twilight could do the Int one, bur none of the three of them have a high enough 'natural'* agi stat for that one, though either would if you swapped at least one prof point to agi
(* the stat before taking equipment into account, so 'base+lv bonus+prof bonus')
(Twilight has 100 base + 60 lv + 0 prof, making her natural stat 160, Heaven is 71 + 60 + 0, a total of 131, you need at least 200 natural for the seals if it still functions the same now as it did back when I did it. At lv60 the first prof bonus gives 191, which would boost any pet over the 200-point threshold)
(or you could find the agi seal, swap a pet that does have the required stat into the party, refresh the page and return to the seal, use the pet, then swap back, that works too)

That helps a lot!

On my first playthrough, I was using the guide. I got confused because they looked so similar.

Then I proceeded to get OWNED by Desius.

Also, how hard is Desius with 1 shield? I don't think I can activate all 4 seals unless I switch one of Twilight's profs.