Game is not playable with the components included (rule book fails at presenting a complete set of rules). However, if you play around with some possible rule sets you will discover that Yetisburg blurs the line between game and activity. In short: choose to attack with Infantry, Cavalry, Artillery, or Yetis. Result: entirely random. As such this doesn't really count as a game.
If you'll notice, the game insists that it's a Vol. One, and that Vol. Two (Dismember the Alamo) is on its way. You'll also notice that no such sequel has been published, nor ever will be published, because this simply fails as a game.