It's easy. When you first come in the game and theres a few people in don't select your character just switch teams. As for th hack, I know someone has made a hack to make you switch teams every like 1 second. I also know theres one for ftb2 where you can customise your seal to be a mercenary or your mercenary to be a seal. They can still target lock you. Theres also one to make you respawn on the seals team if your on the mercenaries or the mercenaries if your on the seals. Then theres the on you can chosse where you respawn instead of the random crap.