The Battleships Universe involves human/pony interactions through the use of interdimensional portals.
Stories listed in reasonably chronological order - Timeline here
1. Battleships are Magic (war/drama)
3.The Truth (crime/drama)
4.Wings of Gold (war/drama)
5.Pinkie's First Christmas on Earth (comedy)
6.Stupid Human Tricks (crime/comedy)
8.Fluttershy Visits Spetsnaz (comedy)
10.Lawers, Guns, and Money (comedy/bromance)
12.The Covert Mare Corps (comedy/drama)
13.As the Sun Rises, So Do We (drama)
14.The Start of Something New (comedy)
15-18 Sail Canvas Quadrilogy (comedy/drama)
Somewhat related side story: The Cutie Mark Crusaders Fly Delta Airlines (comedy) - written by V-pony
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