This is the First Affirmative Rebuttal, or 1AR. Like the other rebuttals, this speech is 6 minutes in college and 5 minutes in college.
The 1AR is one of the hardest speeches in debate. It has to answer the huge Negative Block, covering tremendous ground in very little time. At the same time, it is constrained by the 2AC and is not allowed to make new arguments to positions (unless the Negative Block made new arguments, which is allowed).
Typically, the 1AR will select down and “collapse” to a few arguments. They will perhaps only extend one advantage from their case and will pick 1-2 core 2AC arguments on Negative offcase positions; on those core arguments, they will do further explanation and read more cards.