Not knowing what I would be up against I decided to use Sloan
Gunmage Captain Adept
Round 1 I am up against Denny1. He sprays through the cloud wall to kill the GMCA (to remove shadow fire) and bricks up Denny behind her jacks.
But its not enough and Sloan and 2 hunters get los to her and they shoot her down.
Round 2 and its the Coven, who choose to go second and force me to stay back. They run up and feat denying me doing anything meaningful. The next turn the raiders are jamming up my whole army and I end up losing on scenario.
Round 3 I get another go against the coven again though the list is slightly different. This time I manage to stall out better and shoot down the coven a few turns in.
I ended up second overall, everyone thoroughly enjoyed the format as a great change of pace.
We are looking at running it every month or so but with an added rule that the winner can't use the caster they won with at the next tournament.
If you haven't played rumble before I recommend you give it a try its a really fast paced way to play.
The smaller area of play leads to the armies engaging on the bottom of turn 1, top of 2 if player 1 holds back so fast paced armies are suited well to the format.
I look forward to seeing how the next one turns out, though I will likely try a different Caster and list.