Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Good train set -- lousy mountain

Well, I should have read all the other reviews before buying this one. Now it's off to Toys R Us to try to explain to the customer service employee that no amount of fresh batteries will make this thing explode. I'll try Ray O Vac like someone else suggested. Also, I have a suspicion that the set I have had already been returned -- it didn't come with any instruction book, just a single sheet on how to set up the tracks and insert the batteries. I'm not even sure what this exploding mountain is supposed to do.