REQUIRED CHARACTERS: A rundown
Each of the following characters is most likely essential to success in this chapter. This guide will assume that nobody has been reclassed or promoted yet, and that nobody has any My Castle skills.
Corrin and Effie are undoubtedly going to be your main tanks for this chapter. Both of them should be nigh-untouchable if they've already reached Lv.10 or above, barring bad RNG on Hard. Effie should carry an Iron Lance and a Javelin (or Peri's Lance) at the very least. If possible, a Naginata of some kind will boost her Defense even more, and even possibly enable her to double some enemies. Corrin, as usual, needs only the Dragonstone and Yato. If you're playing on Lunatic, I highly recommend getting an HP and Def tonic for both of them, as well as a Str Tonic for Effie to maximize her chance of one-shotting enemy pegasi.
Jakob/Felicia is going to be Corrin's main support, able to heal them and provide either additional damage or meaty stat boosts depending on the situation. You should have extensive experience with using Corrin and their servant in tandem by now, so I won't go in-depth too much with that here. Remember that you can safely pair them with Corrin and make them the lead fighter sometimes if you need to clear a bunch of ninjas off the map, as Corrin can wall ninjas all day but will rarely kill them on his/her own. If on Lunatic, HP, Def, and Strength tonics are recommended, especially for Felicia.
Niles is your go-to ballista user and pegasus slayer. His high Mobility will allow him to move between key locations on the map with adequate speed. Unfortunately, on Hard he has an occasional tendency to get screwed by the RNG while leveling up - on Lunatic, this thankfully shouldn't be an issue and he can probably one-round KO most enemies with the proper support.
Silas is similar to Niles, a highly mobile unit who can pick up kills on the wings and play aggressively. He has to avoid getting swarmed, but he's actually surprisingly bulky and difficult to kill - he's no tank, but he can hold his own. Like all of your primary attackers, I recommend trying to get him to at least Level 10 before this chapter begins, and filling him up with HP, Def, Speed, and Str tonics. If you can get the Raider Naginata, Silas is the ideal person to use it, as it will allow him to one-round KO sky knights.
Elise is, as usual, your main healer. Be sure NOT to overlook Elise's personal skill: any unit standing adjacent to her will receive a massive damage reduction. This is hugely useful when not fighting ninjas, as she can help tanks achieve that coveted "No Damage" far more often than they ever would on their own, and help squishier units like Beruka and Silas act as a third tank when needed. If you can somehow get a Bloom Festal for Elise before this chapter begins, it should help a lot with keeping her safe by enabling her to heal from 2 range (and therefore safe from ninjas and whatever else might swing an attack over the frontlines.)
Azura is absolutely vital. This guide will often instruct you to use her in very specific ways. She allows Elise to keep up with the healing demands, allows Niles and the tank units to get to the next key position quickly, allows Camilla to launch straight into her killing spree from the word "go" - Azura's role is essentially to make everybody else better, and I don't think this map would be possible without her. If you reclassed Azura before this chapter, you should probably just restart the game or go look for a different guide entirely.
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OPTIONAL CHARACTERS:
You are allowed to bring up to 3 of the following 5 characters onto the map. Using as many as possible is highly recommended, as each can contribute to the battle in their own way.
Arthur's main role, should you bring him into the map, will probably be as dedicated support for Effie. He gives her a shield gauge and a meaty Attack boost, increasing her chances of one-hit KOing the sky knights. When I use Arthur in Chapter 10, I tend to keep him paired with Effie at all times, but if you've been leveling him you might find some value in having him attack with her as well. Honestly, if you're playing Lunatic, I'd be tempted to consider Arthur an essential character to make Effie stronger, but this somewhat depends on your party setup and how many levels Effie's gotten under her belt by this point.
Odin and Nyx are both similar at this point. They'll be relatively weak tome users, mostly useful for taking advantage of the Fire Orb on the left side of the map. If either of them wants to pick up kills directly, they usually need attack support and they often end up putting themselves at risk to do so. Nyx is a much stronger attacker at this point than Odin, though, and also has easier access to Fimbulvetr. Both could use Magic and Skill tonics.
Mozu is interesting. She'll probably be extremely underleveled still by this point, and if you want to use her effectively in this chapter you essentially have to dump 2000g on a Heart Seal (or use the one Haitaka dropped in Chapter 9.) She'll do alright with a bronze bow, but she really wants a Raider Yumi to hit her full potential here, which means you'll be at a disadvantage with her if you've been neglecting My Castle stuff in previous playthroughs (though you could probably go grind for one if you wanted, as it's one of the earlier rewards.) Her main role is basically as a more defensive Niles - she'll mostly want to spend her time using the central ballista when it's safe to do so and patrolling the main plaza for any Sky Knights that slip through the front lines, whom she should have no trouble blowing out of the sky. Tonic her Skill, Strength, and Speed if you're going to use her, even on Hard.
I know nothing whatsoever about Haitaka (the recruitable boss of Chapter 9) or how to use them on this map. If you went out of your way to capture Haitaka and persuade him before starting Chapter 10, congratulations, I hear he's wonderful. I'm sorry I can't provide better advice there.
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NEW ARRIVALS: Camilla and her retainers
How to use these characters in Chapter 10, but also a brief rundown on their future prospects for long-term decisions.
Camilla: undoubtedly the star of this chapter, and quite possibly of all Conquest. Camilla is an incredibly powerful and versatile unit. Though she comes in as a pre-promote, her growths are wonderful and rather than drop off or fall behind she actually only gets stronger from this point on. She's effectively the campaign's biggest "must use" unit, and many of the strategies that you'll develop in later chapters are likely to revolve around Camilla. Rejecting her just because she comes in as a Malig Knight would be a huge mistake. In this chapter, she's a nigh-unstoppable whirlwind of destruction, but will unfortunately only receive ~1 exp for each kill. In Lunatic, she'll also require pair-up support in order to play aggressively.
Beruka is more or less a "proper" wyvern knight, nowhere near as overpowered (or useful) as Camilla. Even if you trained them both equally, Beruka would probably not surpass Camilla in all but the most drastic circumstances. For this reason, she's often swept under the rug, but she's certainly not a bad unit and if you feel like your team could benefit from a second wyvern (and you don't want to use Percy or Seigbert in that role) then there's nothing wrong with using Beruka. In Chapter 10, she's a mediocre but highly mobile unit with poor accuracy and surprisingly weak defenses. She is useful when given proper support, though, and her main utility lies in her ability to cross the map at high speeds like Camilla as well as pick up any houses that you missed in the early stages of the game. Axes are a useful weapon type here, so Beruka is still a useful additional unit for both defensive and aggressive roles in this chapter.
Selena (cough) is the first Mercenary you'll see in this game. Mercenaries are a pretty safe (if slow) all-purpose class that do well on both offense and defense. Their promotions, Hero and Bow Knight, learn some of the best skills in the game and this makes Selena a solid mother for some important children in the long term. On the other hand, if you want to use Selena on her own merits, she's one of the only two first-gen Nohrians who can reclass to Sky Knight, filling a special niche that nobody else really can (since the other is Azura.) Her stats are alright, especially her speed, and she'll perform admirably as a solo or paired unit this way. Unfortunately, in Chapter 10 her best role is probably as pair-up fodder for Camilla (in Lunatic) or Beruka (in Hard,) allowing either of them to perform better at the cost of her own progression.
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THE STRATEGY:
*** The following strategy is based on my own experiences with Fates and is how I, personally, have beaten this chapter every time that I've played it. It's definitely not the only way to beat it; many alternate methods exist that bear no resemblance to this whatsoever. It's just meant to be an outline for those who are struggling.
TURNS 1 and 2:
Examine the map. You have a barricade to the south, a solid stone wall with two obvious entry points - an open one to the right, and a chipped wall to the left that can be broken. In the center is a ballista. Send Corrin and Effie down to the left and right sides to wall those chokepoints with their respective support teams (Jakob/Felicia for Corrin, Arthur/Silas/Mozu/nobody for Effie.) If you're using Mozu, she has a free turn here to use the ballista. Whenever you can use the central ballista, always target Corrin's side of the map - Corrin will be using their Dragonstone almost all of the time, which makes it harder for them to kill enemies without the extra help. With the help of Jakob (and Odin, Mozu, or Nyx if you brought them,) Corrin can start chipping away at the wall; it is generally easier to break this wall before enemies get to it, as this puts you in a better position and lets you start killing the enemies faster.
Silas and Niles, meanwhile should head out to the eastern "wing." Silas should visit the northeast house for a Master Seal, and then he and Niles should both get in position to take care of the archers (and lancers, in Lunatic) coming from that side. Niles can use the ballista over here on the approaching enemies before they arrive, making things a little bit easier for the two of them later on. Starting from Turn 2, Odin/Nyx should man the Fire Orb and start blasting the axemen coming in from the west, so that Beruka can handle them soon.
TURN 3:
Down at the barricade, Corrin, Jakob/Felicia, and Effie should be having little trouble holding off the ground units. Remember that you can clear ninjas on enemy phase by having Jakob/Felicia hold Corrin and fight back with daggers, but you should ONLY do this if all the lancers in range have already been cleared. Silas and Niles should have very little difficulty killing the enemy units that are now finally in range on the eastern side. Don't worry if Niles ends up getting attacked by a lancer in Lunatic, as their accuracy against him is horrible and he should have more than enough HP to take a couple of hits anyway. It's far more important to kill the archers and ensure they'll never reach the ballista or get to safely attack at all.
At the start of this turn, Camilla and her retainers enter from the top of the stage and join the fray. Pair Selena with Beruka (on Hard) or Camilla (on Lunatic) immediately. Send Beruka west - her destination is the house on the left side of the map, which gives 10,000 gold and is therefore obviously the most important house to hit on this playthrough. With Azura's help, Camilla should head southeast and kill the pegasus closest to the southeastern house. You should have Camilla attack this pegasus from the tile directly below, as this will allow Oboro and other land units to suicide against her axe during the next enemy phase. The house next to her contains a Dracoshield. If you can find a way to make Camilla grab this over the next few turns, absolutely feel free to do so, but you'll probably be relying on her to kill a sky knight every turn from now on so it really isn't worth it if you ask me. It's not the last Dracoshield you'll ever see.
TURNS 4, 5, and 6:
For a little while, this chapter becomes pretty easy. Thanks to Camilla, Effie's chokepoint will soon dry up and she'll be free to move beyond the barricade. She should prioritize killing Sky Knights whenever they get close enough to hit with her lances or javelin, but in general she'll just head over to take the pressure off Corrin. Speaking of Corrin, he/she and his/her servant are likely to be absolutely swamped by this point, as the second wave of enemy units should now be closing in from the west. This isn't a problem currently, but it would be good to pair them up at this point and focus on just preventing the lot of them from getting past the barricade. Hopefully, you can get a spare moment to move Corrin or her servant to the nearby house and grab the Dual Club there, a weapon that will be extremely useful for Camilla later on in the campaign. If any pegasi do slip through the barricade, you can have Mozu, Jakob, or Nyx handle it, or use Elise's Rescue or Azura's dance to get Niles back over to the central plaza to pick up the kill. At this point, a couple of pegasi should slip by, but they'll be manageable. Important to note: unless they think they can pick up a kill, Sky Knights on this map will almost always prioritize getting as close to the exit as possible rather than dealing damage. Though this makes them extremely dangerous, it's also a fairly exploitable behavior since it means you can safely put characters like Elise, Azura, and Mozu in their attack range most of the time.
Camilla, once unleashed on the world, should be murdering anything with wings. Any pegasus that tries to fly up on the right side of the map is Camilla's prey, and without fail she should be able to one-shot them all. You should try to keep her cyclone of bloodshed steadily drifting toward the southeastern corner of the map, as this is where the real threat will come from soon. Beruka should play defensively, on the other hand - she's not very tough, so it's good to keep her in a reserved position and let the enemies come to her after being weakened by fire orb damage. If Elise isn't busy elsewhere, having her heal and stand with Beruka will go a long way here. Silas (and Niles, if you're using Mozu) should stay in the northeastern section of the map and handle the second group of archers coming in on that side.
TURNS 7, 8, and 9:
At the end of Turn 6's enemy phase, things get dire. Takumi activates the Dragon Vein, evaporating the harbor and breaking down the previously established system of chokepoints entirely. Meanwhile, in the southeastern corner of the map, a duo of paired Sky Knights spawns with a large cadre of Oni, prepared to make a rapid and violent push for the exit. The latter should be no problem now - if you've been moving Camilla properly, she should now be within range of the first of these pairs, ready to strip away their human shield with yet another decisive blow. Her goal from now on is to follow this squad up the right-hand side of the map as they move for the exit, picking off the pegasi one by one and allowing the oni to fruitlessly throw themselves into the meat grinder. Once they near the top of the map, Silas can meet them in a pincer attack and help pick off whatever's left of them. The new map layout, however, is going to be a much bigger problem for the rest of your units.
As soon as the moat evaporates, the two chokepoints you were defending previously become effectively useless, as Hinata and his troops now move to flank your army from the left-hand riverbed. Though Beruka is already over here, she definitely won't be enough to hold them all at bay. Your new objective is to use Azura to get Effie and Corrin into the two new chokepoints as quickly as possible - one right behind the house where the Dual Club was, and the other at the now-defunct bridge in the northwest corner of the plaza. If either of them isn't already paired up, now would be the time to get them a partner - though Beruka is not available, since she has to help one of them wall the northern bridge so nobody can get through and hurt Elise or Azura.
If Niles is still on the eastern end of the map, get him back to the center ASAP, as this is the part where you'll have the most trouble with pegasi breaking past the front lines and rushing the exit. An immediate and major problem is the paired sky knights that attack alongside Hinata's cadre. It's possible that Effie will be able to kill one of them (Corrin likely couldn't) but if either of the pair is left alive they're going to zip right over the tank's head and either attack a squishy or go for the exit. If you have Niles nearby at the time, he can get next to Effie and finish off the other peg with relative safety. Mozu should not end her turn next to Effie, however, as if she does it's very likely that the ninjas in that group will kill her. If Azura is close, it's possible to send Mozu in for the kill and then pull her right back out again after a dance, but if none of this is possible, you'll just have to hope that the remaining sky knight does not attack one of your weaker units and instead opts to go for the exit as usual. If they do, then they've made a dire mistake and picking up the kill after that is a piece of cake - but of course, it's still a risk.
TURNS 10 and 11:
As long as you wall those western chokepoints in time and keep everyone healed up with Elise, there should be no more trouble from that side of the map. You'll have to accept that this strategy forbids you from going after Takumi, but all he has is an Elixir anyway. You'll get your chance another day.
At the last second, yet another large group of archers and sky knights is going to start closing in from the west, but they're too late. You can simply move Silas and Camilla out of their range, and they won't be able to move fast enough to reach the exit before the chapter ends.
Once Chapter 11's enemy phase is complete, the chapter ends in victory. Corrin will make a show of sparing Takumi, but he refuses to acknowledge their mercy and vows to return with vengeance, complaining all the while about a killer migraine. Camilla congratulates you and tells you not to worry, and together you head for the Rainbow Sage's temple in Notre Sagesse. The next few chapters are honestly breathers - and after all of this, haven't you earned one? Congratulations on beating one of the hardest chapters in Conquest!
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EARLY PROMOTION and ALTERNATIVE CLASSES:
The guide here is designed to work best if nobody has been promoted or class changed before Chapter 10. Despite that, it's pretty common that people will have a slightly different setup by the time they get here, or will want to deliberately reclass/promote somebody to make the chapter easier. I'll attempt to address a handful of the more common and/or useful choices here.
Paladin Jakob: People commonly reclass Jakob to Paladin to simplify Chapter 8 in Lunatic. Though I'm not personally a fan of this one, it makes him pretty versatile in Chapter 10 as well. He can act in basically any role that other melee units can - he'll tank successfully with a pair-up partner, he'll support Corrin almost as well as Butler Jakob does, and can otherwise roam the map picking up kills like a much stronger Silas. You have a lot of freedom with this option, and it's hard to recommend any one place for him over others.
Dread Fighter Jakob / Dark Falcon Felicia: Less common choices, but still incredibly powerful. In these classes, both characters are still best suited to supporting Corrin at the barricade, though they can now do so more aggressively in exchange for their ability to heal.
Strategist Felicia: Like Paladin Jakob, this seems better than Maid Felicia in every way, and unlike Pally Jake she can still fill the same role as before. I'm sure somebody can explain why I'm wrong here, but this honestly seems like a win/win.
Dread Fighter Arthur: Seems to be a fan-favorite choice for an early Dread Fighter. This version of Arthur is much better than his fighter counterpart, able to hold his own as a unit nicely. If you're doing this, I would probably have him trade places with Silas and let the latter support Effie, providing a more aggressive front line and a much needed horse ferry for her while Arthur and Niles head east together.
Samurai Odin: Though significantly stronger in the early game than his magic counterpart, he unfortunately does lose his ability to exploit the Fire Orb. If you're using this version of Odin, you should also bring Nyx or a promoted Elise into the map in order to keep the pressure on. The primary benefit to this is probably the ability to be more violent in the early game on the left side of the map, as Odin should now be able to hold his own somewhat as a fighter instead of always staying behind.
Dark Falcon Odin/Nyx: Literally just a much stronger version of these units. No downsides unless you plan on using them as a parent later.
Sky Knight Azura: If you insist on reclassing her - a very regrettable thing to do if you're serious about beating Conquest - she should be able to help with the anti-air countermeasures in the central plaza, filling a role similar to Mozu. She almost definitely won't have the defenses or HP to go past the frontlines like Camilla and Beruka do, so don't try using her that way unless you're positive it's safe. (This also mostly applies to Sky Knight Selena if you somehow manage to get her a Heart Seal during the chapter.)
Strategist Elise: As with all healers, it's tempting to promote Elise early so she doesn't have to rely on staves for all her EXP. Surprisingly, this works quite well for Elise, and will turn her into a significantly better tome-user than either of the others available to you at the moment. However, since she'll still be pretty frail, the extra firepower does little for us strategically here. It does allow Elise to single-handedly destroy the entire left side of the map until Turn 7, which is probably worth something, but once the dragon vein kicks in she'll mostly have to revert to her healer role for the rest of the chapter. Strategist Elise has applications in subsequent maps, but here she's a bit overkill.
Great Knight Effie: The same as regular Effie, but absurdly overpowered. Obliterates her problems with move and practically guarantees she'll never take any damage. This does, however, come at the cost of rendering all the EXP she gains worthless, and Effie gains a lot of EXP in this chapter. Effie tends to drop off anyway, but I would still only do this early promotion if you're somehow having too much trouble with normal Effie's few shortcomings.
Great Knight/Paladin Silas: A safer and massively superior Silas. This early promotion is highly rewarding in Chapter 10, as Silas can manage large portions of the map by himself and you can keep people like Niles and Beruka moving around the map instead of locked in position. This turns most situations involving Silas into guaranteed locks, and is IMO generally the most useful early promotion you can do for this chapter. HOWEVER! It comes at a huge cost. If you promote Silas early like this, he will be almost 100% GUARANTEED to drop off very quickly, and soon fall far behind the rest of the party. I would only promote Silas this way if you're already planning to replace him in the coming chapters with a character like Sophie, Peri, Xander, Seigbert, etc.
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DIFFERENCES BETWEEN HARD AND LUNATIC:
Because of the way the map is designed, the strategy actually doesn't differ all that much whether you're playing Hard or Lunatic. Though Lunatic has stronger enemies, your party is also likely to be stronger thanks to Lunatic's fixed growth system, and tonics can easily make up the rest of the difference. There's little reason to worry about blowing money on tonics for this chapter, as you get 10,000g here and the next few chapters are much easier anyway. The most significant difference between the two is probably the Sky Knights, who come faster and in greater numbers in Lunatic. I would recommend doing whatever it takes to make sure a mobile unit who can one-round KO them is available at the central plaza at all times, and be cautious about where you place Elise/Azura/Mozu/Nyx so they don't get blindsided by them if they decide to attack. Beyond that, the only real difference is that the enemy units are a bit more numerous, and since this strategy largely revolves around tanking and chokepoints that's basically irrelevant. Incidentally, this is why I recommend pairing Selena with Camilla on Lunatic - the horde of enemies finally gets a bit too big for Camilla to handle alone, but some extra Defense and a shield gauge easily fixes that issue and Beruka does fine without a partner as long as Elise babies her.