Leviathan is a ten-part Star Trek Fleet Command mission chain in which you help Starfleet and the crew of the USS Enterprise stop the Doomsday creature, a planet killer heading for the Sol system. Every part has a recommended level of 28. The chain starts with a rendezvous in Gemet and sends you through Federation, Klingon, Tholian and Romulan space, with warp to complete between 17 and 25. Headline rewards are shards for TOS Pavel Chekov and TOS Montgomery Scott, 3★ ship parts, rare refined materials and a steady flow of Parsteel. The fights are all near 100,000 strength, so a level 28 fleet handles the whole chain.
Leviathan at a glance
| Part | Recommended level | Warp to complete | Key reward |
|---|---|---|---|
| Leviathan Part 1 | 28 | 25 | 2,215,000 Parsteel, 16 3★ Uncommon Refined Gas |
| Leviathan Part 2 | 28 | 20 | 771,000 Parsteel, 6 3★ Uncommon Refined Ore |
| Leviathan Part 3 | 28 | 23 | 8 3★ Uncommon Refined Crystal, Tritanium |
| Leviathan Part 4 | 28 | 17 | 500 Premium Recruit Token, 119,000 Officer XP |
| Leviathan Part 5 | 28 | 20 | TOS Pavel Chekov shards |
| Leviathan Part 6 | 28 | 20 | 370 3★ Survey Parts, 50 Latinum |
| Leviathan Part 7 | 28 | 22 | 1,878,000 Parsteel, Tritanium, Dilithium |
| Leviathan Part 8 | 28 | 25 | 150 each of 3★ Battleship, Interceptor and Explorer Parts |
| Leviathan Part 9 | 28 | 20 | 3★ Rare Refined Gas, Ore and Crystal |
| Leviathan Part 10 | 28 | 18 | TOS Montgomery Scott shards |
Leviathan Part 1
The Doomsday creature threatens Sol and Starfleet needs to evacuate the system. You meet the Enterprise, get briefed by Admiral Strode and then guard the evacuation fleet.
- Rendezvous with the USS Enterprise in Gemet.
- Attend the briefing with Admiral Strode on Starbase 74 (Gemet).
- Track the evacuation fleet to Risette.
- Defeat the Rigellian Assailant (Risette, enemy strength about 104,274).
- Donate 275,000 Tritanium to the evacuation fleet.
- Ensure the evacuation fleet reaches Anymansbak safely (Losti).
Warp to complete: 25.
Rewards: 16 × 3★ Uncommon Refined Gas, 2,215,000 Parsteel, 66,000 Dilithium.
Leviathan Part 2
Starfleet wants the Klingons in the fight against the creature. They are not keen at first, so you have to get past a guard before they listen.
- Attend the tactical briefing on Starbase 74 (Gemet).
- Attempt to enlist the aid of the Klingon Empire (Phelan).
- Defeat the Klingon Guard (Phelan, enemy strength about 101,520).
- Approach the Klingons on Wesk (Phelan).
- Bring the Klingons to Elya.
Warp to complete: 20.
Rewards: 6 × 3★ Uncommon Refined Ore, 771,000 Parsteel, 114,000 Tritanium.
Leviathan Part 3
A distress signal from the USS Constellation leads you to Skarrl, where survivors need rescuing.
- Investigate the distress signal in Skarrl.
- Defeat 12 hostiles of level 28 or higher.
- Beam the remaining survivors onto your bridge (Skarrl).
- Bring the Constellation crew to Starbase 80 (Xerxes).
- Return to your Station.
Warp to complete: 23.
Rewards: 8 × 3★ Uncommon Refined Crystal, 163,000 Tritanium, 33,000 Dilithium.
Leviathan Part 4
Scotty wants his counterpart’s notes from Delta Vega. You fly him there, power the facility with raw gas and fend off an attacker. This part has the shortest warp in the chain.
- Bring Scotty to Delta Vega (Vulcan).
- Donate 500 G3 Raw Gas to power the facility.
- Defeat the attacker (Vulcan, enemy strength about 101,520).
- Return to your Station.
Warp to complete: 17.
Rewards: 500 Premium Recruit Token, 200 Ship XP, 119,000 Officer XP.
Leviathan Part 5
You try to recruit the Tholian Assembly against the planet killer. Their guard has to be disabled before they agree to meet.
- Approach Tholian territory (Beta Assembly).
- Disable the Tholian guard’s vessel (Beta Assembly, enemy strength about 102,720).
- Meet with the Tholians on their Outpost (Beta Assembly).
- Return to your Station.
Warp to complete: 20.
Rewards: 5 × TOS Pavel Chekov shards, 11 × 15 Minute Repair Speed Up, 1 × 1 Day Peace Shield, 500 Federation Recruit Token.
Leviathan Part 6
Leevoigh can help the Tholians, but she needs support. This part is all travel plus one Parsteel payment to the Breen.
- Rendezvous with Leevoigh on P’Jem.
- Bring Leevoigh to the Breen Outpost (New Dozaria).
- Pay 750,000 Parsteel to the Breen for a temperature suit.
- Bring Leevoigh to the lab on Sekay (S’mtharz).
- Return to your Station.
Warp to complete: 20.
Rewards: 370 × 3★ Survey Parts, 50 Latinum.
Leviathan Part 7
Scotty wants the data core of a Progenitor Sphere. You feed the Sphere Dilithium and then get clear before it blows.
- Investigate the Progenitor Sphere’s signal (Arcadion).
- Beam 75,000 Dilithium to the Sphere’s ionization chamber.
- Escape the Sphere’s blast radius (Niawillen).
- Return to your Station.
Warp to complete: 22.
Rewards: 1,878,000 Parsteel, 277,000 Tritanium, 56,000 Dilithium.
Leviathan Part 8
Maia opens a rift to send a message to the USS Enterprise, and you keep the testing site safe while she works.
- Bring Maia and Scotty to the testing site (Risette).
- Defeat 12 hostiles of level 28 or higher.
- Defeat the Mysterious Assailant (Risette, enemy strength about 102,720).
- Attend the tactical briefing on Starbase 74 (Gemet).
Warp to complete: 25.
Rewards: 150 × 3★ Battleship Parts, 150 × 3★ Interceptor Parts, 150 × 3★ Explorer Parts.
Leviathan Part 9
The showdown with the Doomsday threat. You push toward the creature through two systems, beating a Doomsday Worm in each, until Maia can deploy the stasis field.
- Get closer to the Doomsday creature (Honsao).
- Defeat the Doomsday Worm (Honsao, enemy strength about 104,274).
- Continue advancing towards the Doomsday creature (Maya).
- Defeat the Doomsday Worm (Maya, enemy strength about 104,274).
- Get Maia into position to deploy the stasis field (Tenzen-1029).
Warp to complete: 20.
Rewards: 1 × 3★ Rare Refined Gas, 1 × 3★ Rare Refined Ore, 1 × 3★ Rare Refined Crystal.
Leviathan Part 10
With the creature stopped, the Enterprise crew needs to go home to their own timeline. You escort them through three Romulan fights in Sufiday and back to Starbase 74.
- Escort the USS Enterprise to Sufiday.
- Defeat the Romulan Attacker (Sufiday, enemy strength about 102,720).
- Defeat the Romulan Guard (Sufiday, enemy strength about 101,520).
- Defeat Subcommander Letik (Sufiday, enemy strength about 104,274).
- Escort the USS Enterprise to Starbase 74 (Gemet).
- Return to your Station.
Warp to complete: 18.
Rewards: 5 × TOS Montgomery Scott shards, 130 × 15 Minute Speed Up, 1 × 1 Day Peace Shield, 500 Federation Recruit Token.
Tips for completing Leviathan
Leviathan belongs to TOS Arc 3, and Hidden Agendas is the chain that follows it in the same arc. Each part unlocks the next, so work through them in order.
Warp is never the problem here. The highest warp to complete is 25, in Parts 1 and 8, and Part 4 needs only 17. What varies is the kind of work each part asks for, so read ahead and have the right resource ready.
Four parts have a donation or payment. Part 1 asks for 275,000 Tritanium, Part 4 for 500 G3 Raw Gas, Part 6 for 750,000 Parsteel and Part 7 for 75,000 Dilithium. The raw gas is the one most players do not have sitting in the bank, so mine it before you reach Part 4.
Every named enemy in the chain sits between about 101,520 and 104,274 strength. Parts 3 and 8 add 12 hostiles of level 28 or higher with no fixed system, so any eligible hostile counts. Part 10 stacks three fights in a row in Sufiday, which is the one place where a repair between battles helps.
The officer shards come at the midpoint and the end: TOS Pavel Chekov in Part 5 and TOS Montgomery Scott in Part 10. Browse the mission guide for the other TOS chains.
Are the Leviathan rewards worth it?
Yes. At level 28 the chain pays two sets of TOS officer shards, 450 3★ ship parts split across three hull types, 370 3★ Survey Parts, a full set of 3★ rare refined materials and more than 4.8M Parsteel. The costs are modest and the enemies stay close to 100,000 strength throughout, so it is a comfortable run for a mid-level fleet.
