Crystal domain

Crystal domain Clerics call on the innate power of crystals and gemstones to aid allies and hinder foes. They can attack foes, but also aid allies at the same time, effectively making their allies twice as strong compared to their enemies

Heavy armor proficiency

You gain proficiency with heavy armor

Crystalline reversal

Also at 1st level, you can cause a mote of crystal to appear and heal for the damage of the attack. When a creature is attacked within 30 feet of you that you can see, you can use your reaction to heal the creature for the damage of the attack (max of 2 x cleric level).

You can use this feature once at first level, twice at 5th, three times at 11th, and four time at 17th. You regain all expended uses when you finish a long rest.

Channel Divinity: Glittering Vortex

Starting at 2nd level, you can use your Channel Divinity to Make 4 motes of crystal surround you, along with a burst of glittering light

As an action, you present your holy symbol, and gain 4 motes of crystal revolving around you. One mote can be expended per bonus action, when expended these motes fly toward a target within 60ft that you can see, the motes can either do 2d4+your wisdom modifier force damage or heal 2d4 +your wisdom modifier hit points. alternatively you can spend a full action to use 2 motes instead of 1.

Additionally, each hostile creature within 5 feet of you must make a Dexterity saving throw. A creature takes radiant damage equal to 2d6 + your cleric level on a failed saving throw, and half as much damage on a successful one. A creature that has total cover from you is not affected.

Improved Glittering Vortex

Starting at 6th level, your Glittering vortex now summons 8 motes, and its initial AOE is 10ft

Enhanced crystals

At 8th level, you can empower your crystals to make them do more damage. Once on each of your turns when you hit a creature with a crystalline spell, you can cause the attack to deal an extra 1d8 force damage. When you reach 14th level, the extra damage increases to 2d8.

Glittering Soul

Starting at 17th level you gain resistance to force damage

Also, as you have one crystal mote left from your glittering vortex you can use your bonus action to create an amount of crystal motes equal to a spell slot that you expend. So if you use a 2nd level spell slot you regain 2 crystal motes.