For the Year 1 weapon, see Vex Mythoclast (Year 1) .
...a causal loop within the weapon's mechanism, suggesting that the firing process somehow binds space and time into...
― In-game description
Vex Mythoclast is an exotic fusion rifle . It can only be obtained as a random drop after killing Atheon in the 390 Light version of Vault of Glass . It is the only fusion rifle that is equipped in the primary weapon slot.
Sources Vex Mythoclast can be retrieved from one of the following activities/vendors:
Upgrades Vex Mythoclast can be upgraded with the following perks:
Column 0
Solar Damage
This weapon causes Solar Damage.
Timeless Mythoclast
This weapon has no charge time. It fires a single bolt with each trigger pull.
Infuse
Consume a more powerful Weapon to boost the Attack value of this Weapon.
Column 1
Aggressive Ballistics
More predictable recoil.
Enhanced Impact.
Shorter range and more recoil.
Linear Compensator
More predictable recoil.
Slight boosts to range and Impact.
More recoil.
Smart Drift Control
Predictable and controllable recoil.
Penalty to range.
Column 2
Zen Moment
Causing damage with this weapon increases its stability.
Column 3
Extended Mag
A larger magazine.
Send It
Increases range and accuracy.
Harder to handle.
Decreases carried Ammo capacity.
Lightweight
When held, this weapon grants +2 character Agility.
Column 4
Crowd Control
Kills with this weapon grant bonus damage for a short time.
Column 5
Ornament: Chronoshot
Applies an Ornament to this weapon.
Gallery
Chronoshot ornament applied to Vex Mythoclast.
References 
