It's a 2 part test, the first consists of logic questions that are clumsily worded, but not very hard. The second part is an artificial language constructed to be similar to the grammar of spanish. It is supposed to test your ability to learn spanish. If you already speak spanish you can just take a spanish test. I haven't had the energy yet to get into it much, but I don't think it is as hard as it looks.
It is kind of strange.... the Border Patrol Academy is 5 months long, and the FBI agent academy is only 4.5, and way longer than the secret service which is only 11 weeks.
Of course, the FBI and Secret service entry requirements are a bit more stringent.