Ok, so Thor told me about this and I have no idea why he didn't report it.
It's often fun finding those bugs, but it's totally lame to abuse them without reporting.

I didn't check on this but the coop leaderboard is proof enough.

1) Apperently when you use death march (2x) on your own VIP it does die but you don't lose the game.
2) when you log in the game more than once you can join your own game and play arena alone. (No idea how exactly, maybe with 4 different internet connections) Then you can choose a position without the vip and win easily.

Please check on this and fix it. And I'd like to know how exactly it was possible to choose own cards in a sealed match.

damn I thought I wrote this bugs! forgot to submit err...
Thor didn't write it because I told him I did

I found out the multi-login room could be done in any mission, the constructed in sealed also reported.
Also the 5 turn win arena bug, that I really don't know how it happen

Also: Special forces at VIP, he dies and you are free to win ( mission 8) this worked a few random times for me