The pieces shown on the March 1987 Flyer do not fit easily, the Piscean Warrior and Dark Elf disappeared, and the others were renamed into the 40k canon.
The 1988 Rogue Trader Part Flyers gathered all the existing 40k related pieces together and included the solid based fishmen seen below, other quick conversions of existing pieces had been used during playtesting and are sometimes found on the market. The Pirate is a conversion of a C01 Fighter from Compendium 3.
