Back when I needed to grind missions, I would put a bunch of mission cards in with a single card that needed to be leveled up. Then I would win with my mission cards and no pill all the others. And I would actually TRY to lose so that my un evoed card would stay unevoed as long as possible so I could keep doing my missions..
@HipHoppa Whenever I see someone doing that I try my best to ruin their mission. (Well, back when I had to use training for masses of cards) When I encountered it, I just always saw it as exploitative; "accomplishing" missions against people who are using unleveled cards.
Missions should be disabled in training modes in my opinion.