HELLO EVERYONE AND WELCOME TO MY NOT 204TH ANALYSIS, NOT NEXT TO THE 205TH AND 206TH ONES WHICH ARE RUBY AND EMERALD RESPECTIVELY, FEATURING XIRON THE QUARTZ.
Overview: It honestly pisses me off to do my 267th analysis on this guy because it triggers my sense of order so much. But I digress - there is absolutely no reason to get Quartz over Emerald, let alone Ruby, because his weapon-specific moves have no effects attached to them whatsoever and his Speed is bad for a denier. He does have some tools that can work, but overall, Quartz is not very good compared to modern deniers.

Builds:
Monsters that have access to Group 4 skills will have a slightly different build path. I will list the most viable builds for each Rank since some moves in Group 4 are pivotal to some sets' success. The monster's role will likely remain the same, however, so this won't be exhaustingly long as I won't repeat the same things.

Rank 0:
Moves:
-Total Exhaustion
-Major Exhaustion
-High Wage
-Control Dice
Runes: 3 Team Speed
Mutant Rune options: Team Speed&Team Life
Relics: Masks and Staves

Build Explanation:
Total Exhaustion denies a single enemy by draining all of its Stamina. Major Exhaustion instead brings all enemies closer to recharging by draining 50% of their Stamina. You can also follow Total Exhaustion with this to deny your initial target twice, since they will go to 50% after recharging. High Wage applies a random deny effect to a single enemy alongside Stamina Leak. Lastly, Control Dice attempts to deny all enemies, having a 50% chance of applying a random deny effect to its targets.
Despite being a denier, Quartz doesn't benefit much from having 3 Speed at this point, so 3 Team Speed with Team Life Mutations is a better choice for a spread.

Rank 1: Quartz learns "Mineral Blood" at this level, a single target CD Activation.
Moves:
-Total Exhaustion
-Major Exhaustion
-Mineral Blood
-Control Dice
Runes and Mutant Runes are the same as given above.

Build Explanation:
Mineral Blood is a more reliable single target deny than High Wage, plus it can deny Artifacts as well, making it a must have move.

Rank 2: Quartz learns "Laying Odds" at this level, a Base 55 Magic AOE that applies Stamina Leak and a random deny effect to all enemies.
Moves:
-Total Exhaustion
-Laying Odds
-Mineral Blood
-Control Dice/Major Exhaustion
Runes: 3 Speed
Mutant Rune options: Speed&Life

Build Explanation:
With Laying Odds, Quartz becomes a denier. It's a strong deny move if RNG favors you, and a regular deny at worst. In the last slot, run Control Dice if you feel like the chance is worth taking, or Major Exhaustion otherwise.
3 Speed with Life Mutations becomes the spread now that he's a denier.

Rank 3: Quartz learns "Quartz Explosion" at this level, a Base 45 Magic AOE.
This move provides absolutely nothing and you shouldn't run it.

Teammate Options: For Teammate Options , check out this article.

Countering Xiron the Quartz: For Counter options, check out this article.