LogFAQs > #986312557

Battle Before Dawn on HHM probably takes the cake for worst Fog of War Fire Emblem map. As Green Units (that need to survive to get the Gaiden Chapter + 1 that has to survive to beat the Chapter period) that you can't control are almost equally a terrible mechanic, together they make for a horrendous chapter.

-It's possible for the RNG to screw over Jaffar and he dies before you have a chance to back him up.
-If Nino takes damage, she will flee before using an item to heal. She can run right into Ursula's (the really powerful chapter boss) Bolting Range and will get killed instantly.
-Trying to rush too fast to save either of them risks getting ganged up on by too many units, which can get a unit killed.
-Zephiel (the guy who has to survive but you wish he didn't to prevent the horrible events preceding FE6 from happening) also gets killed by a Hero unit early on if you don't get a unit to him fast (Turn 6 is when he starts getting attacked IIRC).
-Maxime (a sub-boss) also has absolutely insane stats on this difficulty. Just...no other unit got a stat boost as large as he got. Just damn.
-The biggest f*** you to the player is Ursula's AI though. She won't move for most of the Chapter. However, she will move starting Turn 13 without any warning or prompting. Hopefully a surprise Bolting or Elfire won't lead to you suddenly losing a unit like has happened for a lot of players (myself included). Hope you don't mind losing two hours of progress!!!

Both FE5 (which doesn't even let you see map terrain) and FE6 also have some nasty FOW maps, but I don't remember any of them being as bad as Battle Before Dawn. Lots of FE5 (late game) is oddly enough warp skipped (even in a not speed run) so the latter ones aren't that bad (god help the person who plays 24X blind though) and FE6's FOW maps mostly let you play at a slow pace if you want.