There are two main reasons why Season 2 is roughly half the length of the other seasons:
If you are diving into the world of Attack on Titan (Shingeki no Kyojin) for the first time, or you just finished the action-packed first season, you might be looking at the episode list for Season 2 and doing a double-take. how many episodes are in attack on titan season 2
But if you remember that Season 1 had 25 episodes, you are probably asking a very important follow-up question: Why is it so short? There are two main reasons why Season 2