win a round with a “toughness” based build, where the attack suddenly spiraled out of control
Yes, this is how it feels when a combo is successfully assembled, congratulations for the win.
with the mage … you can’t win the game, since expensive spells deplete your mana much faster.
Although it is quite true that you must find some way to replenish mana with mage, it is not as hard as it seems, especially on easy difficulty where you only have to reach stage 12. The most important hint for the beginner Mage is to accumulate “Gather Magic” cards in hand before playing them all in single turn. In general, while basic Warrior builds focus on “rush attack”, basic Mage builds often must defend and delay for a few turns to get optimal value from the battle.
When player unlocks card upgrades, initial mana replenishment becomes much more reliable by just upgrading “Gather Magic” cards.