All Our Yesterdays (Last Unicorn)
Time travels sourcebook.

Summary 
From the back cover

Back to the future…

… ahead to the past…

… sideways to today!

From the ancient humanoids of four billion B.C. to the Kelvan Invasion of the 123rd century, all time stands open before you. All Our Yesterdays is the complete guide to time travel in the world of Star Trek roleplaying, covering everything from time travel techniques such as the slingshot effect and Borg temporal vortices to the rifts in space-time which snare unwary travelers. Overlays and organizational details make members of the Department of Temporal Investigations and other transtemporal characters ready to play. There's a chronology of the Star Trek universe, guides for Narrating time travel episodes and avoiding (or inviting) temporal paradox, 29th century Federation Timeships and fearsome Borg spheres, and teasers for episodes stretched all across the galaxy and throughout its history.

Cross your 23rd century Star Trek Roleplaying Game characters over into your Next Generation or Deep Space Nine series (or vice versa), or run a pure time travel series. The first of our Expanded Universe sourcebooks combines the entire cosmos of Star Trek roleplaying opportunities. This book includes:

 Eight episode seeds, three series seeds for Expanded Universe play, and nine parallel histories accessible by subspace rift or Romulan treachery.
 Directives (including the Temporal Prime Directive), guidelines, mission types, technology, history, and organization for the Department of Temporal Investigations – enough information to run an entire DTI series.
 Four new overlays and eight new DTI Tours of Duty, plus early life background history packages, new advantages and disadvantages, new and expanded life skills (including psionic skills) for time travel, and more.
 Seven new ships and five new alien species descriptions (including the Krenim, the Travelers, and an expanded Devidian description).

When time flies, you're having fun! Get started now with All Our Yesterdays: The Time Travel Sourcebook!

Contents 
All Our Yesterdays is a sourcebook for the Last Unicorn Games Star Trek RPG.

 Introduction
 Temporal Physics
 Parallels
 A History of Time Travel
 The Department of Temporal Investigations
 DTI Characters
 Others in Time
 Timeships
 Narrating Time Travel

Background information 
 This was one of the last two Star Trek RPG books (the other being "Raiders, Renegades & Rogues") published by Last Unicorn Games, as the company was purchased by Wizards of the Coast around the same time. Paramount then awarded the RPG license to Decipher.

References

Starships 
Epoch-class timeship
USS Aeon
USS Baktun
USS Century
USS Epoch
USS Eternity
USS Generation
USS Kapla
USS Millennium
Thucydides-class timeship
Originating in the 2370s, under the command of the Department of Temporal Investigations.DTI ThucydidesDTI DurantDTI HerodotusDTI Livy (lost)
Wells (Polarity) class timeship
USS CharmUSS Polarity''
USS Relativity

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