The Thrynn are a living stereotype. They resemble large lizards and add the letter ‘s’ when they speak (“...yesssss?”, “alliesssssss”). The Earth term of “slimy reptile” fits, as they are not to be trusted, as they are usually seeking plutonium, but if they offer an exchange for fuel if a spacefaring captain has any plutonium on their ship, the captain would be able to get a lot more money if they were to sell it to the Arth space station instead. They also boast that they have a black box that they will exchange for a lot of fuel, claiming it has all kinds of functions, but after the exchange is made and a crew member examines the box, they will find it actually has no function whatsoever.
The Thrynn also could state during an encounter that other races that “cower” should all “die”.
Thrynn Scoutships weigh 200 tons. They have a shield class of two and are armed with phasers. They are known to carry Endurium, copper, zinc and magnesium, which, with their lack of onboard plutonium, makes sense why they ask for it when encountering others in space.