Dead Messenger (Vox Obscura Mission)

• Trinary Vision: a one-shot grenade launcher whose projectiles release three waves when they hit the ground.
• The Fundamentals: an alternate weapon action changes the damage type between Void, Arc and Solar, and the weapon gets a damage boost when you gain a matching elemental buff or apply a matching debuff.
• Traits: Thresh, Unrelenting or Demolitionist in the second trait column, with seven launcher barrels to pick from.
• Catalyst: Turnabout, an overshield for breaking a combatant's shield or a Guardian's Super with the launcher.

Vox Obscura is one of the exotic missions Bungie lists among the available ones, and the catalyst record names Vox Obscura in Pinnacle Ops as its source. Update 9.7.0 tweaked the special reload timing and fixed The Fundamentals so it can be activated more than once per life, and it realigned the components of crafted copies with their weapon level.

• Dead Messenger from the Vox Obscura mission.
• Additional Options: Add Dead Messenger Catalyst, and Unlock every Crafting Trait. Extras: Self-play (Sherpa).

• Exotic missions are Pinnacle Ops for up to three players; some depend on an expansion, so the manager checks yours.

Which damage types can it use?

Void, Arc and Solar. The alternate weapon action cycles through them.

Is the catalyst needed for the Turnabout effect?

Yes. Turnabout is the catalyst perk, so the weapon has it only with the catalyst applied.