Here's what's missing or changed: – FF IV: THE AFTER YEARS Review

Many reviews already mention there are no challenge dungeons in this game, making all the grinding in all the chapters but the last worthless. But there's more bad news: they did not mention that all the bonus bosses in the final dungeon from other cameo FF games are gone and replaced by recycled IV bosses (including ultima weapon). And the fact that you can't farm adamantite to get adamant armor sets for the entire team, but just one set (adamantites are final rewards in challenge dungeons). Plus, you also don't get the developers office (or maybe it's a different location that no one's discovered) where you could trade in items to get more goodies. One of the worst things they did was mess with the final dungeon's layout. It's bad enough the tailed monsters that drop rare tails can be found in a single room in the dungeon, but what's worse is the monster shows up only in 1/4 phase of the moon. Determining which monster is where is practically impossible without a guide, which are all wrong because iOS version is different. This problem could easily be remedied with a siren that triggers rare encounters in a given room, but for some idiotic reason, sirens have been taken out of the game!!!
Review by ZenMasterZ on FF IV: THE AFTER YEARS.