There should be a market building where you can sell one resources and get another, but if you trade you get half as much resources (e.g 200,000 twigs becomes 100,000 pebbles)
@congregation101 - if you pay 100 war bonds then there is no lose as buying 4 blight packs is 100 war bonds, but in a tourny you get the same amount of cards but a chance to get 2 more and also get some warbonds
if the devs remove the energy bar then this game would get extremely boring, as the game would just become a grind game, meaning that there is no challenge to it