YMMV / Fire Emblem: The Four Kings

• Goddamned Bats: Nomads almost always carry short bows that will quickly wear down most units with their speed. Shelby and Walter will casually No-Sell their attacks but it will be rare for them to be able to hit them back at range hard enough to get rid of one, forcing you to slow down to consistently deal with them. Later maps in Walter's route tend to throw them at you in groups of 3-4.
  • Fleets are significantly more common here than in the base game, being able to fire shots at you from far out of most units' effective ranges. Many units will die from a hit from these combined with any other enemies' attack, so you always have to play conservatively whenever they're around. Which is almost always. Thankfully they never move around.
• Good Bad Bugs: Preferred weapons that grant stat bonuses will do so even in arenas. This allows some characters to gain great advantages in it despite being forced to wield other weapons. Vin in particular will always be unhittable by his enemies, ensuring easy wins and money.
  • You can gain skills from another character's preferred weapon by just having it at the top of your inventory, allowing characters to benefit from them so long as they never initiate a direct attack. A good example is giving Dorian Elias’s preferred weapon to give him Canto+, letting him reposition after refreshing someone.
  • The unit Locritus can occasionally learn a random skill from the builder system defaults throughout the story. It's impossible to control but can lead to him gaining Game-Breaker powers such as Canto+ or Lancebreaker.
  • Lionel's sabre has tripled might against not only sword-wielding classes, but also against breakable walls.
• Low-Tier Letdown: Ron very often finds himself on the lower end of usefulness for players due to his poor accuracy, being locked to lances without any Crit Boost to compensate and very situational preferred weapon.
• That One Attack: Bolting is all over Lionel's route and the lategame. This poses a serious threat to Zachary due to his low resistance and him being forced on every map after this point. Later chapters push it to the point where these tomes will OHKO him unless you actively protect him or hold him back until the users are dealt with. Some maps even have multiple bolting sages that you will have to work through before Zachary can take care of his utilities.
• That One Level: Chapter 18. Multiple ballistae and Bolting sages, numerous fast enemies, and waves upon waves of wyverns come together to put any progress to a halt as you attempt to reach a single tile where you can draw in and fight the boss. The wyverns also frequently approach over mountains where you can't effectively attack them, and your only available flier is incapable of taking on these groups by himself. It took until a recent update for the chapter to be toned down (the frequency of the flier reinforcements was reduced, and there are far fewer Nomads to deal with).
• They Wasted a Perfectly Good Plot: Ava's heritage and her connection to Teodros could have given her a solid arc after being relegated to Walter's emotional support and love interest for most of the game. However, this information is introduced in Chapter 23 and ignored until after defeating the final boss, where she admits that her emotions don't matter and becomes Teodros' queen without any insight to her thought process.