The troll army started with these chaps, the original sons of Bragg, Boomhowler and Company. This was the first batch of trolls due to them being mercs, and they accept payment in ale.
Boomhowler has proven his usefulness multiple times, not for hitting anything, but for bogging down enemy troops. His unit is a tarpit anyone can hire (almost).
I decided that all the trolls who trace their lineage to the great fellcaller wear the red tartans and have an affinity for brass armour.
There is a distinct lack of sculpts for this unit, complicated by the lack of pieces. More bits would allow more variations, which is something the mutlipart plastic kits have right. My plan for the next four is to mix bits with kriel warriors and such.
Of course, this doesn't mean they aren't fun minis. Like true mercs, they each carry a small keg and those guns scream close combat.