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Faction Khitomer.png Impossibility of Reason
EP - Impossibility of Reason.png
Followed by:
May 14, 2019
1,041 Expertise icon.png
You will receive the following reward:

Impossibility of Reason is the second of two missions released with Rise of Discovery featuring Gabriel Lorca and Ellen Landry. Following from the loss of Aakar, the player finds themselves stranded on the ice moon of Priors 5D with Lorca and Landry, trying to survive against the elements and the Klingons hunting them.


Mission text[]

DSC Starfleet[]

This Klingon computer virus is giving me a bad feeling about things. With J'Ula and House Mo'Kai involved, I think we're looking at a serious new effort to capture or destroy high-value Starfleet targets... ships, personnel, or even entire planets.

Let's rendezvous with the Buran as fast as we're able. That virus is already in her systems, and after what we just dealt with, I'm guessing the Klingons aren't done with my ship just yet.


The Priors World simulation has provided some very interesting data. Starfleet Command wants to expand on what we've learned, and the latest simulation should help with that.

Your participation in this simulation is important, though the subject matter may be... sensitive. We're asking you to step into the aftermath of the battle at Priors World. You'll be dealing with the actions of J'Ula and her forces there, under extreme conditions. Good luck.


Analysis of the Priors World simulation data continues. Several agencies, including Imperial Intelligence, want to expand on that data, and they've created another simulation to do so.

Your participation in this simulation is required. The simulation will require you to step into a situation all true warriors should be prepared to face - the aftermath of defeat.

I trust you will rise to this challenge and face it with honor. Qapla'!


The data acquired from the Priors World tactical simulation has been quite... enlightening. Our analysts, in their tireless search for knowledge, have requested further study on the matter. And, thus, another simulation has been created.

Your participation in this simulation will be most informative. I should warn you, however. The simulation will place you directly into the aftermath of the battle at Priors World... on the losing side. You'll be dealing with the actions of J'Ula and her forces, under extreme conditions. May the Elements guide you well.


I bring you greetings from the Founders. May you always serve them well!

A great amount of fascinating data has been obtained from the resent Priors World tactical simulation. Naturally, the quest for knowledge is a never-ending one, and so a new simulation has been commissioned. Your participation in the newest simulation is required, of course.

It's important to note that the subject matter may be... challenging for a soldier of the Dominion. It will place you into an unfamiliar situation - that of defeat, in the aftermath of the battle at Priors World. You'll contend with the forces of J'Ula, under extreme conditions. Honor the Founders. Victory is Life.


Get Captain Lorca to Safety.


  • Captain on the Brink
  • Iced In
    • Go To Priors 5d
    • Fetch Supplies from the Shuttle
    • Emergency Transport Capt. Lorca
    • Head for Shelter
      • Situation Update
      • Fetch the Fallen Shuttle Components
      • Drive Off Ice Beasts
      • Fetch the Fallen Shuttle Components
    • Check on Lorca
    • Re-heat Rock with Your Weapon
    • Make Camp
  • Snow Place Like Home
    • Talk to Lorca
    • Talk to the Team
    • Talk to Landry
    • Search Fumaroles for materials (3)
    • Exit the Fumaroles
    • Return to the Cave
    • Give Supplies to Kerwin
    • Place Explosive Charges
    • Talk to Patel
    • Camp for the Night
  • Frozen Heart
    • Talk to Kerwin
    • Ambush Klingons at Fumaroles
      • Defeat Jackal Mastiffs
      • Take Up Ambush Spots on High Ground
      • Ambush Klingons from Above
    • Fall Back to the Cave
    • Reach Lorca
    • Defend the Cave
      • Melt a Hole Out the Back
      • Escape Out the Back
      • Talk to Lorca
  • Contact Command



House Mo'Kai[]


NPC starships[]



Icon Name Description How to Get Points
Agents of Yesterday Arc icon.png Ice Ice Baby Activated a Subspace Party Amplifier in the cave on Priors 5d After you first enter the cave, activate a [Subspace Party Amplifier] just before you "Check on Lorca."

Note: The mission does not give you a Subspace Party Amplifier. You need to purchase one before starting the mission.



For a walkthrough of this mission, visit the Walkthrough page.

Mission Replay[]

This mission is repeatable through Mission Replay, although the Rewards for completing will be reduced. Items scale to a player appropriate level (Scaling Rewards), as follows:

Level Rank Experience Point icon.png Expertise icon.png Mark <>
1–9 Lieutenant 780 195 II
10–19 Lt. Commander 1158 675 IV
20–29 Commander 1552 1338 VI
30–39 Captain 1743 1878 VIII
40–49 Rear Admiral 1935 1856 X
50+ Vice Admiral+ 1935 2148 XI


  • During the Defend the Cave you must allow the House Mo'kai invaders to pass the opening where the bomb is placed. If they are killed before passing the bomb's point mission will not advance.

External links[]

v · d · e
Storyline Missions      
All Starfleet Factions Starfleet-only
Tutorial DSC Starfleet only “Graduation Day”“Routine Maneuvers”“Trial by Fire”“The Shadow Knows”“Children of War”“Reporting In”
TOS Starfleet only “I Sing of Arms”“Search and Rescue”“Bull by the Horns”“Dislodging Klingons”“The Taurean Affair”“Earthward Bound”
25th century Starfleet only “Graduation Day”“Training Cruise”“Field Promotions”“Communication Breakdown”“Assimilation of the Innocent”
Agents of Yesterday TOS Starfleet only “Explore Earth Spacedock”“In the Shadow of Cestus”“Painful Omens”“Return to Babel”“Tangled Webs”“The Battle of Caleb IV”
Klingon War “Welcome to Earth Spacedock”“Diplomatic Orders”“Stranded In Space”“Researcher Rescue”“Secret Orders”“The Doomsday Device”“The Galaxy at Large”
Romulan Mystery “Heading Out”“Empress Sela”“Desperate Measures”“Shadow Play”“Taris”
Faction KDF.png Klingon Defense Force-only
Tutorial “End of Watch”“Red Alert!”“Intruder Alert”“Challenge for Command”“Your New Command”“Journey to Qo'noS”
Empire “Duties of Command”“The Hunt is On”“Space Chase”“Manhunt”“Friend or Foe”
Warzone “Bringing Down the House”“The House Always Wins”
Vigilance “Mars, the Bringer of War”“Alpha”
Fek'Ihri Return “Blood of the Empire”“Destiny”“Afterlife”
Faction Romulan Republic.png Romulan Republic-only
Tutorial “A Day on the Farm”“A Day in the Sun”“Virinat, Invaded”“Flight from Virinat”
From the Ashes “Explore the Flotilla”“The Helix”“Crossroads at Crateris”“Gasko Blues”“The Search for New Romulus”“Turning Point”“Neutral No More”
Allies “The Price of Neutrality”“Memory Lane”“Bigger Picture”“Smash and Grab”“Tradecraft”
In Shadows “An Inside Job”“Enemy Action”“Sleepers”“Cloak and Dagger”“Revelation”“Mind Game”
Wasteland “Secrets of Nimbus”“The Lost City of Paradise”“Blind Men Tell All Tales”“The Undying”“A Fistful of Gorn”“Installation 18”
Vengeance “Voice of the Voiceless”“Abducted”“Small Packages”“Last Stand”“The Best Defense”“Turnabout”“Devil's Choice”
Freedom “Toward Freedom”
Faction Dominion.png Dominion-only
Engineered for War “Hunt”“Ceremony”“Turn the Tide”
Faction Khitomer.png Cross-faction
Cloaked Intentions “The Vault”“Mine Enemy”“Frozen”“Coliseum”“Cutting the Cord”“Darkness Before the Dawn”
Cardassian Struggle “Lost and Found”“Spoils of War”“Jabberwocky”“The Factory”“The New Link”
Borg Advance “Task Force Operations”“Report on Borg Activities”“Where Angels Fear to Tread”“A Gathering Darkness”“Assimilation”“Fluid Dynamics”
New Romulus “New Romulus Aid”“Staging Area”“Hidden Camera”“Warehouse”“Mountain Base”“Secret Shuttle Codes”“Overgrown Caves”“Web Access”“Latest Findings”“The Power Source”“Secrets of the Ancients”
Solanae Dyson Sphere “Sphere of Influence”“Circles within Circles”“Supply Woes”“The Contested Zone”“The Omega Standoff”“Tower Control”“A Step Between Stars”“Fluidic Destruction”“Surface Tension”
Delta Quadrant “Escalation”“Mindscape”“Reunion”“Friends in Unlikely Places”“Revelations”“Enemies in All the Usual Places”“All That Glitters”“The Kobali Front”“Capture the Flag”“The Dragon's Deceit”“Alliances”“Know Your Enemies”“Revolution”“Taking Care of Enemies”“Takedown”“What's Left Behind”“Dust to Dust”
Iconian War “Uneasy Allies”“Blood of Ancients”“Delta Flight”“House Pegh”“Time in a Bottle”“Broken Circle”“Butterfly”“Midnight”
Yesterday's War “Temporal Ambassador”“The Once and Future Agent”“The Core of the Matter”“Vorgon Conclusions”“Terminal Expanse”“Survivor”
Future Proof “Sunrise”“Stormbound”“Time and Tide”“The Temporal Front”“Temporal Reckoning”“Ragnarok”
New Frontiers “Echoes of Light”“Of Signs and Portents”“Mirrors and Smoke”“Brushfire”“Beyond the Nexus”“Melting Pot”“Scylla and Charybdis”“The Renegade's Regret”
Gamma Quadrant “Storm Clouds Gather”“Armistice”“The Search”“Doomed to Repeat”“Quark's Lucky Seven”“Tenebris Torquent”“Home”
Age of Discovery “The Plausibility of the Possible”“Impossibility of Reason”“Secrets”“Downfall”
J'Ula's Discovery “Para Pacem”“Illusion of Communication”“Beneath the Skin”“Sentinels”“Rescue and Search”“Within The Briars”“The Ninth Rule”“Ruins of Doom”“The Measure of Morality (Part 1)”“The Measure of Morality (Part 2)”
Klingon Civil War “The Centre Cannot Hold”“The Khitomer Discord”“Partisans”“Knowledge is Power”“Leap of Faith”“Warriors of the Empire”“A Day Long Remembered”
Terran Gambit “Firewall”“Red Shift”
Some missions may appear in alternative orders for some factions.
Mission available Side Content: The Galaxy at Large
Spectres “Spectres”“Skirmish”“Spin the Wheel”“What Lies Beneath”“Everything Old is New”“Night of the Comet”
Wasteland “Secrets of Nimbus”“The Lost City of Paradise”“Blind Men Tell All Tales”“The Undying”“A Fistful of Gorn”“Installation 18”
(Still part of main episode progression for Romulan Republic players.)
Lost Dominion: The 2800 “Lost Dominion”“Second Wave”“Of Bajor”“Operation Gamma”“Facility 4028”“Boldly They Rode”
Cold War “Cold War (wrapper)”“Cold Call”“Out in the Cold”“Cold Comfort”“Cold Case”“Cold Storage”
Delta Quadrant “Kobali Crisis Act I”“Kobali Crisis Act II”“Kobali Crisis Act III”
See also: Featured episodePatrolRemoved MissionsTask Force Operation