Citadel Trilogy
by Kevin Tumlinson
4.00 · 6 ratings
violent-conflict · adult · fiction · military · book · sci-fi · action-adventure · technothriller · time-travel · audiobook · apocalyptic
Citadel Trilogy: Similar series
Catteni
by Anne McCaffrey
3.96 · 124 ratings
adult · invasion · romance · violent-conflict · female-author · first-contact · space-opera · space-travel · sci-fi · aliens · fiction · action-adventure · futuristic · dystopia · space · audiobook · colonization · other-world · female-mc · survival
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Rho Agenda Chronological
by Richard Phillips
4.10 · 219 ratings
sci-fi · violent-conflict · action-adventure · fiction · audiobook · book · technothriller · aliens · suspense · first-contact · mystery · military · adult · invasion · space-opera · political-intrigue · espionage · politics · space · space-travel
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Legacy Fleet
by Nick Webb
4.16 · 149 ratings
space-travel · colonization · supernatural · aliens · exploration · fiction · invasion · book · first-contact · military · adult · space-fleet · space · violent-conflict · soldiers · sci-fi · galactic-empire · space-opera · technothriller · action-adventure
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Island in the Sea of Time
by S.M. Stirling
4.00 · 54 ratings
apocalyptic · war · wlw · action-adventure · fiction · alternate-history · romantic-love · sci-fi · violent-conflict · historical · adult · military · book · historical-fiction · time-travel · post-apocalyptic · audiobook · steampunk · industrial-era · alternate-universe
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Area 51
by Bob Mayer
3.95 · 192 ratings
paranormal · book · sci-fi · violent-conflict · adult · first-contact · war · action-adventure · aliens · fiction · military · audiobook · soldiers · political-intrigue · conspiracies · technothriller · supernatural · mystery · alternate-history · 21st-century
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Dimension Space
by Dean M. Cole
4.02 · 48 ratings
book · technothriller · invasion · post-apocalyptic · dystopia · audiobook · action-adventure · fiction · aliens · apocalyptic · hard-sci-fi · violent-conflict · adult · military · first-contact · space-opera · sci-fi · time-travel · alternate-history · multiverse
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Axis of Time
by John Birmingham
3.95 · 95 ratings
action-adventure · fiction · alternate-history · book · time-travel · war · violent-conflict · historical · military · historical-fiction · 20th-century · sci-fi · technothriller · adult · espionage · ww2 · audiobook · cold-war · noir · political-intrigue
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Rise of the Jain
by Neal Asher
4.20 · 44 ratings
space · ai · book · invasion · violent-conflict · space-fleet · adult · military · first-contact · space-opera · soldiers · sci-fi · action-adventure · aliens · fiction · hard-sci-fi · audiobook · technothriller · mystery · investigator
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Imperium
by B.V. Larson
3.62 · 58 ratings
space · violent-conflict · hard-sci-fi · invasion · book · aliens · fiction · galactic-empire · sci-fi · space-opera · first-contact · audiobook · military · adult · technothriller · soldiers · space-fleet · colonization · action-adventure · horror
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Post-Human
by David Simpson
3.74 · 138 ratings
fiction · sci-fi · dystopia · cyberpunk · action-adventure · crime · space · post-apocalyptic · book · adult · audiobook · technothriller · time-travel · violent-conflict · apocalyptic · box-set · ai · anthologies · supernatural · young-adult
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Assiti Shards
by Eric Flint
3.90 · 375 ratings
sci-fi · historical-fiction · adult · historical · alternate-history · action-adventure · fiction · time-travel · book · violent-conflict · military · audiobook · early-modern · war · political-intrigue · single-planet · politics · alternate-universe · family · survival
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1632 Universe/Ring of Fire
by Eric Flint
3.90 · 417 ratings
fiction · action-adventure · alternate-history · historical · historical-fiction · sci-fi · time-travel · adult · violent-conflict · book · early-modern · military · audiobook · war · single-planet · political-intrigue · alternate-universe · politics · survival · family
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Atlantis
by Bob Mayer
3.84 · 65 ratings
book · military · adult · violent-conflict · paranormal · sci-fi · fiction · action-adventure · war · alternate-history · soldiers · time-travel · technothriller · suspense · conspiracies · political-intrigue · mystery · audiobook · urban-fantasy · aliens
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The Henry Gallant Saga
by H. Peter Alesso
4.05 · 58 ratings
galactic-empire · action-adventure · aliens · fiction · invasion · book · time-travel · military · genetic-engineering · violent-conflict · space-fleet · sci-fi · space-opera · colonization · first-contact · war · space · adult · young-adult · paranormal
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First Salik War
by Jean Johnson
4.00 · 28 ratings
space · paranormal · book · invasion · adult · magic · romance · violent-conflict · first-contact · military · space-opera · sci-fi · fiction · aliens · action-adventure · female-mc · war · dystopia · cyberpunk · politics
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Star Trek: Deep Space Nine: Millenium
by Judith Reeves-Stevens
4.00 · 34 ratings
action-adventure · aliens · fiction · invasion · book · military · genetic-engineering · adult · violent-conflict · sci-fi · space-opera · drama · time-travel · space · pulp · hard-sci-fi · futuristic · audiobook · far-future · box-set
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Donovan
by W. Michael Gear
4.21 · 42 ratings
action-adventure · fiction · hard-sci-fi · space-opera · sci-fi · audiobook · adult · book · aliens · futuristic · colonization · dystopia · space · violent-conflict · horror · military · time-travel · survival · first-contact · space-travel
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The Pax Humana Saga
by Endi Webb
3.97 · 34 ratings
fiction · sci-fi · aliens · military · violent-conflict · space-fleet · adult · soldiers · space-opera · colonization · book · space · galactic-empire · genetic-engineering · action-adventure · exploration · first-contact · space-travel · supernatural · invasion
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Amaranthe
by G.S. Jennsen
4.32 · 122 ratings
cyberpunk · colonization · space-opera · sci-fi · violent-conflict · first-contact · military · aliens · fiction · galactic-empire · invasion · space-travel · space-fleet · exploration · action-adventure · space · adult · soldiers · book · genetic-engineering
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Area 51: Time Patrol
by Bob Mayer
4.07 · 27 ratings
time-travel · book · alternate-history · fiction · action-adventure · sci-fi · adult · technothriller · myths · historical · male-mc · military · violent-conflict · historical-fiction · conspiracies · political-intrigue · ww2 · space · suspense · 20th-century
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Jim Chapel
by David Wellington
3.70 · 23 ratings
suspense · violent-conflict · adult · military · horror · book · crime · action-adventure · mystery · fiction · technothriller · political-intrigue · thriller · conspiracies · sci-fi · paranormal · espionage · supernatural · audiobook · 21st-century
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The Lone Star Reloaded
by Drew McGunn
4.35 · 17 ratings
action-adventure · fiction · alternate-history · book · time-travel · violent-conflict · adult · military · historical-fiction · sci-fi · space · galactic-empire · portal-travel · war · historical
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Kaiserkrieger
by Dirk van den Boom
3.87 · 15 ratings
adult · fiction · action-adventure · alternate-history · time-travel · book · sci-fi · historical · historical-fiction · military · violent-conflict · single-planet
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Citadel Trilogy
by Kevin Tumlinson
4.00 · 6 ratings
violent-conflict · adult · fiction · military · book · sci-fi · action-adventure · technothriller · time-travel · audiobook · apocalyptic
All books in this series ❯