FunATuns is right about having a limited amount of time. Since there is a finite amount of gold you can collect there is a hard limit on how long the game is.
Gold will be the hardest thing to balance. You can't fire minions, and it would be a great idea if you could. It would also be great if the minions held the gold you spent on them. So once they die in battle you can recover the funds you spent. This way you could at least recycle the gold. Which makes the cost of failure better and adds a risk to attacking. Great for when Keeper vs. Keeper comes in.
