These mods add crystals that grant certain powers. There are 4 in total:

The Shadow Crystal

The Light Crystal

The Chaos Crystal

The Astral Crystal

The Shadow Crystal:
It allows you to become invisible and fast for 5 seconds. When interacted with, it produces an explosion of soul particles. In return, other players will see you with items in your hand and armor.

The Light Crystal:
It allows you to project a beam of light that inflicts 10 hearts of damage. In return, its cooldown is much longer.

The Chaos Crystal:
It allows you to create a powerful Force effect. It produces an explosion of flame particles upon interaction. In return, its cooldown is much longer.

The Astral Crystal:
It allows you to dash in the direction you're facing, in return for taking fall damage.

Explanation :

To craft them you will need to go to The End, there you will find Crystellia ores.

With These Fragments you will need "Element" there are 4, here they are:

Shadows: To get shadows you will need the scanner and use it during the night, you will gain 1 shadow

Lights: To get lights you will need the scanner and use it during the day, you will gain 1 light

Chaos: To get chaos you will need the scanner and use it in the nether

Astral : To get astral you will need the scanner and use it above layer 200

Scaner :

All Craft :

 This Is The block You Need To Assemble All Fragment of crystals.

Tongs Are Needed To Craft The Crystallizer

The Keyboard is needed to craft the crystallizer

You right clicked in at a certain location (Day, Night, Nether, >200)

Exemple Crystals Craft Parts:

With all this you will be able to craft a crystal of the chosen element.

Crystallizer GUI:

And It's All !! 

If you want to help me suggest ideas for mods or things to add to my mods or bugs, already suggest them in the comments of the mod in question or on this Discord server: Discord Server