Discussion of how to deal with abilities or spells which cost xp.
Since the tournament does not effect the campaign, there is no penalty to using these spells / abilities.
One adjustment will be that within the tournament, although you gain no xp from the matches, you can lose xp via these abilities and spells. That xp lost, does carry over. Once you reach a point where losing more xp would cost you a level, depending on the spell, one of two things happen:
1 - You can no longer use those spells and abilities, since you are not allowed to lose a level
2 - You lose a level and continue