I found that trying to find players to play against is getting more difficult, so I'm playing in the Training.
For this, I chose one of the big damage dealers, in my case Drogos as one of his choices is 35% extra missile damage, and with the hits being explosive, you can easily get kills without meaning to, although his missiles are slow(ish) and he only fires 6 before having to reload.
Go into a Training/Seige game, it doesn't matter if you have AI or people on your team, but the enemy AI tend to be a bit dumb, so just fire away - keep on using his
attacks as well as his missiles, plus his special is an "insta-kill" as long as it hits.
I got this and Hard Carry during the same game, just don't expect to get them during a TDM game, go either for the other 2 game types and keep on pounding away!
At the end of the game I ended up with over 30 kills and somewhere around 200,000 damage!