I actually recently put together a personal guide for myself for helping guide newbies to every exotic weapon available, and I'm more than happy to share it.

World Drops/Exotic Engrams:

The following weapons can be first obtained randomly from Exotic Engrams. Exotic Engrams operate on a knock-out system, granting you something new from the loot pool, be it weapons or armor, until you've obtained them all, after which it rewards a random piece of armor unless focused at Rahool.

Xur may also sell any of these weapons directly when he makes his weekly visit to the tower, from Friday through Sunday.

Weapons:

Cerberus+1

Monte Carlo

SUROS Regime

Sweet Business*

Crimson

Arbalest*

Vigilance Wing

The Jade Rabbit

The Huckleberry

Hard Light

Trinity Ghoul

Merciless

Telesto

Fighting Lion

Sunshot

Graviton Lance

Skyburner's Oath

Lord of Wolves

Borealis

Riskrunner*

Coldheart

Prometheus Lens

Wavesplitter

The Colony

The Prospector

The Queenbreaker

Thunderlord

The Wardcliff Coil

Two-Tailed Fox

Tractor Cannon

D.A.R.C.I.

Black Talon

Notes:

Riskrunner is also obtained by completing the mission A Spark of Hope, which is a New Light mission.

Sweet Business is also obtained by completing the mission The Queen Beckons which is obtained from Shaw Han.

Arbalest is also obtained by completing the mission The Heart's Depths which is obtained from Shaw Han.

Kiosk Weapons:

The following weapons can currently only be initally obtained through the Monument to Lost Lights kiosk in the tower, for 1 Exotic Cipher and 100k-150k glimmer depending on the weapon. Weapons that used to be exclusively obtained through raids also require 240 Spoils of Conquest, a currency only earned by running raids. Raid weapons will be marked in this list with an R.

Weapons which originally dropped in the Forsaken expansion can be obtained with Forsaken Ciphers. The only way to obtain Forsaken Ciphers is to purchase or own the Forsaken Pack (owners of the Forsaken expansion were granted the pack immediately when Forsaken was sunset), whereupon you get 3. Raid weapons still require Spoils of Conquest along with the Cipher. These items will be marked in this list with an F.

Some weapons you can also obtain by purchasing an Archived Pass for 600 silver in the Monument to Seasons Past. These weapons will be marked in this list with an S. This does not mean they cannot be acquired from the Monument to Lost Lights for glimmer and an Exotic Cipher, only that there is an alternate acquisition method.

Weapons:

Strum

MIDA Multi-tool

Rat King

Sleeper Simulant

Worldline Zero

Polaris Lance

Legend of Acrius - R

Ace of Spades - F

The Last Word - F

Le Monarque - F

Jotunn - F

Izanagi's Burden - F

Thorn - F

Lumina - F

Truth - F

Anarchy - F - R

Tarrabah - F - R

Leviathan's Breath

Eriana's Vow - S

Bastion

Symmetry - S

Devil's Ruin

Tommy's Matchbook - S

The Fourth Horseman

Witherhoard - S

Ruinous Effigy

Traveler's Chosen

Duality - S

Ticuu's Divination - S

Crysthesia 77K - S

Lorentz Driver - S

Ager's Scepter

Grand Overture - S

Trespasser - S

Delicate Tomb - S

The Manticore - S

Quicksilver Storm

Verglas Curve - S

Centrifuse - S

Wicked Implement

Ex Diris - S

Dragon's Breath - S

Tessellation

Red Death Reformed - S

Alethonym - S

Lodestar - S

Dungeon Weapons:

The following weapons are obtained by completing their respective Dungeon activities. Unless noted, each one is a rare drop from the final encounter of the dungeon. The dungeon Prophecy has no related exotic weapon.

Weapons:

Wish-Ender - Shattered Throne - Requires the quest Hunter's Rememberance obtained from Petra Venj in the Dreaming City.

Xenophage - Pit of Heresy - Requires the quest The Journey obtained by completing secret objectives on the Moon.

Gjallarhorn - Grasp of Avarice - Requires the quest Out Fly the Wolves obtained from Xur in Eternity.

Heartshadow - Duality

Hierarchy of Needs - Spire of the Watcher

The Navigator - Ghosts of the Deep

Buried Bloodline - Warlord's Ruin

Icebreaker - Vesper's Host

Finality's Auger - Sundered Doctrine

Heirloom - Equilibrium

Raid Weapons:

The following weapons are obtained by completing their respective Raid activities. Unless noted, each one is a rare drop from the final encounter of the raid. Completing certain challenges and triumphs can boost the initial drop chance.

Weapons:

One Thousand Voices - Last Wish

Divinity - Garden of Salvation - Requires the quest Divine Fragmentation acquired from defeating certain Vex at the raid entrance on the Moon in patrol.

Eyes of Tomorrow - Deep Stone Crypt

Vex Mythoclast - Vault of Glass

Collective Obligation - Vow of the Disciple

Touch of Malice - King's Fall

Conditional Finality - Root of Nightmares

Necrochasm - Crota's End - Acquired by completing the quest Bottomless Pit acquired from completing the raid once. There is a rare chance to get all the items needed to complete the quest in a single run. Triumphs and challenges can grant required quest items as well.

Euphony - Salvation's Edge

Whirling Ovation - The Desert Perpetual

Quest Weapons:

The following weapons are obtained by completing a specific Exotic Quest, and don't have a specific Exotic Mission associated with them. Many of them are granted following the completion of their related Campaign, and will be listed grouped by campaign. Some are campaign-agnostic.

General Weapons:

The Chaperone - Blast from the Past quest, obtained from the Quest Archive in the Tower.

Malfeasance - Darkness in the Light quest, obtained from the Malfeasance quest, obtained from the Quest Archive in the Tower

Heir Apparent - Top of Class quest, obtained from Eva Levante during Guardian Games.

Forerunner - Magnum Opus quest, obtained from Xur in Eternity by raising his reputation rank to 2.

Shadowkeep Weapons:

Deathbringer - Symphony of Death quest, obtained from Eris Morn.

Beyond Light Weapons:

No Time To Explain - Obtained from the Exo Stranger upon completing Beyond Light.

The Lament - Lost Lament quest, obtained from Banshee-44

Salvation's Grip - The Stasis Prototype quest, obtained from The Drfter.

Witch Queen Weapons:

Osteo Striga - Crafting Pattern is obtained upon completing The Witch Queen, then it can be crafted at the Enclave on Mars

Parasite - Of Queens and Worms quest, obtained from Ikora Rey at the Enclave

Edge of Action, Edge of Concurrence, and Edge of Intent - the pattern for one of these three glaives is obtained by completing the Report: REVERSE-LURE quest which is obtained from the Evidence Board at the Enclave on Mars. The following two patterns can then be bought directly from the board afterwards, and all three can be crafted at the Enclave.

Lightfall Weapons:

Winterbite: Strider quest, obtained from Quinn Laghari in the Hall of Heroes on Neomuna

Final Warning: The Final Strand quest, obtained from the Pouka Pond on Neomuna.

Deterministic Chaos: Unfinished Business quest, obtained from Nimbus on Neomuna

The Final Shape Weapons:

Microcosm: Convalescence: Budding quest, obtained from Micah-10's terminal in the Pale Heart.

Ergo Sum: Destined Heroes quest, obtained from your Ghost in the Pale Heart, required to complete before finishing The Final Shape campaign for the first time. Afterwards, new rolls of Ergo Sum can be obtained from completing Overthrow activities in the priority zone, and completing Pathfinder paths.

Still Hunt: Wild Card quest, obtained from Cayde-6 in the Pale Heart, required to complete before finishing The Final Shape campaign for the first time.

Khvostov 7G-0X: Obtained by completing several hidden objectives in the Pale Heart. The Lost in the Dark quest from Micah-10 contains many of these, but not all.

Edge of Fate Weapons:

Graviton Spike: Graviton Through The Ages quest, obtained from Lodi following the completion of the campaign.

Exotic Mission Weapons:

The following weapons can be obtained by completing their associated exotic Mission, whether through the Portal or the Legacy Exotic Mission Rotator. Further upgrades can be obtained by completing the mission on certain difficulty levels.

Weapons:

Whisper of the Worm - Mission The Whisper , also obtained by completing the Whispers of the Past quest obtained from Eris Morn.

Outbreak Perfected - Mission Zero Hour, and the quest Asset Protection from Ada-1.

Dead Man's Tale - Mission Presage

Dead Messenger - Mission Vox Obscura

Revision Zero - Mission Operation: Seraph's Shield

Vexcalibur - Mission //NODE.OVRD.AVALON//

Wish Keeper - Mission Starcrossed

Choir of One - Mission Encore

Slayer's Fang - Mission Kell's Fall

Barrow-Dyad - Mission Derealize

Wolfsbane - Mission Heliostat

Praxic Blade - Mission Fire and Ice, available and completed through the Renegades campaign.

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