Children of Zodiarcs

This achievement requires you to roll all possible dice on a single roll, and can only be done toward the end of the game so that you can equip 6 dice and have cards with 3 bonus blue dice available.

The 17 dice you need are:
6 equipped dice
3 bonus blue dice on card (any red attack card with 3 blue dice will do)
4 bonus positive effect dice (Bonus Shard, 2x Bonus Star, Bonus Shield)
3 cursed negative effect dice (2x Cursed Star, Cursed Shard)
1 Negative Evasion Shard.

You can set this up fully with your own team. Skirmishes will randomly change every time you load the game and if you choose the 4th map along the path and spawn in the bottom area (as opposed to the middle of the map) then if you let the 3 enemies come to you the others will never move and you can peacefully set this up. Effects only last for 3 turns but they're pretty simple to keep active once you've gotten the 2x Bonus Star dice added. I suggest you equip dice with lots of stars just to make things easier and less prone to chance as all of these effects require stars.

Keep your decks small here, we just want to get the required stats up quickly, churning through useless cards wastes time. The required cards are

Xero: Meditative Subroutine, Cellular Regeneration, Invigorate
Brice: Heartless Cruelty
Nahmi: Just you Wait, Will to Live, Into the Darkness.

Now onto implementing this.
On the bottom of map 4 let the enemies come to you, kill them, now you're free to do whatever you want. Put your allies in a T so you can cast on all 3 at the same time.

Xero should use Meditative Subroutine to get into the Guardian state. Invigorate or Cellular Regeneration is how you get Evasion. You'll need 4 stars on Cellular Regeneration to give everyone 2 bonus green star dice.

Nahmi uses Will to live will give everyone 1 green shard die (requires 3 stars on a roll, so easier to get once Xero buffed everyone with stars). You will also need to stealth and attack a teammate from stealth with Just you Wait to add the bonus shield die to everyone.

Once you have all 4 bonus green dice up + evasion on your characters, Brice will cast Heartless Cruelty onto a character to add the 3 cursed shard dice. Now have any character attack another character with an attack card with 3 blue dice. I found this easier than hoping an enemy would throw up evasion.

The achievement will pop before you even roll the dice, you just need to select the card and have all the dice appear. You can back out at that point, so if you're missing something you'll be able to make any adjustments before being locked in.