I'm calling them 'Companions' and not 'wives' both because it makes this concept less of a headache to talk about across the games (Each game has different terminology for what's mostly basically the same mechanic) and because it feels less creepy that way.
Note that I'm not going to be covering the children you can get. If you really care, Gamebanshee has lists for which children can be gotten from whom as well as what those children do. I don't care, because which ones you get are entirely random (Removing any possibility of meaningful analysis), and anyway the children both eat equipment slots and for the most part their effects are dubious in their utility. If you get Gandalf, good for you, your Mage is going to be a monster in the late-game, but otherwise you can almost certainly do better with an actual piece of equipment. It's not even practical to savescum the children, because the game actually rolls all the children for all the Companions at the very beginning of the game, where if your run gets Ambrella from Feanora and you don't like that result loading an earlier save and trying again will always result in Feanora giving birth to Ambrella. The only savescumming you can realistically do is to drop a save before marriage and then if you don't like the child load the save and marry someone else, which is a huge waste of time. My recommendation is ignore the entire thing, because it's actively detrimental to good play. (And also kind of creepy!)
Thankfully, all the later games dump children as a game mechanic entirely.
The following list is ordered roughly in terms of when you can first acquire each Companion, for reference.
Rina/Zombie Rina
Rina: +1 to the Speed and Initiative of Robbers, Marauders, Pirates, and Sea Dogs
Zombie Rina: +1 to the Speed and Initiative of Undead.
Equipment slots: Armor, Artifact, Belt, Boots.
Zombie Rina is amazing, with bar none the most useful innate effect of any of the Companions. If you're going to all-in on Dark Commander and rule the world with the Undead, Zombie Rina is your gal-pal. She has the added bonus that she will never, ever pester you about children.
Regular Rina's effect is... eeeeh. It's the same bonus, but on a smaller list, and the pseudo-race of outlaws isn't even a particularly great unit set. Sea Dogs can be pretty awesome, and indeed I like to run them in the early game with Rina before I've gotten access to a good supply of Undead units, but Pirates are really just terrible and Robbers and Marauders are... well, they have uses, but they're not great combat pieces, and Rina's boosts only somewhat help push them into being good combat pieces. (The fact that Royal Snakes still outclass them when they've got her boosts, unless you also stack on Jackboots, makes it difficult to actually justify using them. Especially since Snake Boots bolster snakes in a similar way to Jackboots boosting criminals)
Her equipment slot list is serviceable, but she shares with Mirabella the dubious distinction of being the only Companion with no multi-purpose equipment slots, which can be a bit frustrating. On the other hand, in my opinion these are all the most important and beneficial slot types other than Weapons -Artifact is where a lot of your exotic, powerful effects that are useful at any scale are, Armor is where you get a lot of your Resistance effects, Boots tend to provide even more Speed or other utility effects that are nice/amazing to have (If a bit specialized, quite often), and Belt is where you get your Concentration equipment. (... assuming you luck into it. Otherwise Belts are... mostly pretty mediocre) Regalia, Helmets, and Shields have some useful effects, but in my experience don't really have the same sort of stand-out options, and so her lacking them isn't necessarily a big deal.
The fact that Rina/Zombie Rina can be gotten at nearly the beginning of the game with minimal hoop-jumping helps endears her to me as well.
Also worth noting is that you can switch between Rina's forms at will. She's really basically a 2-in-1 deal, which is particularly appreciated given that dismissing a Companion means never again having access to them in that run. As such, being able to switch modes, even if one of those modes is low-benefit, is pretty nice in context.
Narratively, Rina's story is... something I struggle to really find something interesting to say about. There's some observations I could make about how, for instance, Zombie Rina's behavior regarding the ring is evocative of Gollum, or I could talk some about how Rina's story is creepy, but then again it's pretty obvious that it's meant to be creepy. But then again, part of how it's creepy is the things the game doesn't do: there's no option to permanently cure Rina of her zombification, for example. But then yet again, that's probably in part growing out of how her zombie state is a game mechanic...
Oddly, I think her story is actually my favorite of the Companions regardless of my mixed feelings about it. The other Companions in The Legend are invariably boring as characters with boring stories. Rina is really the only one that genuinely comes across like there was an effort to write a human being reacting realistically to their circumstances, who happens to be an option for marriage, and is also one of only two options that really feels like it's doing something meaningful with the fantasy setting.
Feanora/Frog-form Feanora
Human-form: +3 to Intellect
Frog-form: +100% Attack for all allied spiders and snakes. (ie Cave Spiders, Venomous Spiders, Fire Spiders, Undead Spiders, Snakes, Swamp Snakes, and Royal Snakes)
Equipment slots: Artifact, Artifact, Artifact/Belt, Helmet.
There's only two real reasons to go for Feanora. Either you're fishing for Gandalf, in which case you're entirely ignoring my advice about not messing with the children system, or you want to stack all the Artifacts. Which is a completely legitimate goal, especially for a Mage! Artifacts is basically the best equipment slot bar arguably Weapons.
Frog form's boost to Snakes and Spiders is actually pretty nifty, as Royal Snakes and to a lesser extent basic Snakes are really good units, and Royal Snakes in particular are a good fit to a Mage due to their high Initiative helping give you control over casting timing, while actually being a really good combat piece in their own right, unlike some of the other high-Initiative units out there. (eg Devilfish) If you get lucky with items (Snake Boots), you can have some dominating early-game snake-supported armies!
Human form's boost to Intellect is... eh. It's nice, but the higher your Intellect gets the less useful her boost in particular matters. I wish she'd been given a better-scaling effect, honestly. It does at least have the advantage of not requiring you use a particular army composition to benefit from it.
In any event, she's the other early-game Companion, and she's pretty solid. I prefer Zombie Rina, but Feanora is decent enough.
Worth noting is that Feanora's transformation isn't nearly as convenient as Rina's. She'll join you in human form, and if you ignore her for long enough (It's based on battles fought for the 'timer') she'll eventually revert to frog form. If you then want to switch her back to human form you can do it instantly at any time, but... the whole thing is kind of inconvenient, since her spider/snake specialty is the sort of thing you might find yourself wishing to suddenly be able to take advantage of (eg because you just got access to Royal Snakes) and having to wait is annoying. If some piece of this worked in reverse, you could manually switch over to the spider/snake bonus when you suddenly decided you wanted to, then run around until it began to lose its luster, wait for her to time out, and change your army once she transformed to her Intellect boost. When I've used Feanora, what I've done is let her lapse into frog form ASAP, run Snakes and Royal Snakes for a while (Ideally, with Snake Boots), and once I've largely run that course switch her to human form and never let her stay in frog form ever again. It's still kind of annoying, and I'm glad none of the later games had an equivalent Companion.
Though taking a moment to acknowledge the child mechanic, I'm puzzled and disappointed the game explicitly established that Froguses result from frogs turned into humans who give birth, gave you the option to marry exactly such a girl and have children with her, and then didn't actually give you Frogus children. I've long wondered if the child mechanic was originally imagined as something more robust, because only one Companion doesn't bring up the conceptual possibility of not-entirely-human children by their nature, and yet the child mechanic is... strangely generic, like something that got slapped together in a rush. It's too bad, if so. I'd have been a lot less creeped out by the whole marriage mechanic's handling if it was being used as the foundation for Crazy Fantasy Eugenics.
I'm aware that's vaguely ironic-sounding, and stand by it anyway.
Narratively, I sort of like the idea of Feanora's little story, because of how it's playing around with the 'kiss frog get prince(ss)' trope, but the actual end result feels pretty creepy. The game doesn't really suggest that these frog princesses have some automatic political importance or anything, so the marriage doesn't really come across as political, yet it's still this odd thing of a girl(-frog) being grateful enough to marry you because... uuuuh...
... yeah.
Bit creepy, with the 'saving a girl's friends so she'll marry you' thing.
Mirabella
+100% Attack for allied Pirates, Sea Dogs, Robbers, and Marauders.
Equipment slots: Weapon, Belt, Boots, Regalia.
There's people that like Mirabella, and I have no idea why. Her boosts are ridiculously narrow and as your Attack climbs the boosts will more and more often cap out, reducing their actual value, and her equipment list is only notable for the fact that there's exactly one other Companion with a Weapon slot. I suppose if you really want to be wielding an extra Weapon before you're ridiculously far into the game, Mirabella is kind of the default choice, but it seems like a tremendous waste. Rina boosts the exact same list of units with a much more useful set of boosts that remains fully relevant for all time, and then can go Zombie anytime you like to benefit a whole other list of much better units. The fact that Mirabella is locked behind a mid-game boss fight that is unreasonable to actually beat when you gain access to it is the icing on the cake -Mirabella is early-mid-game in terms of theoretical access, but usually you're going to be waiting for much longer than that to convince Pirate Red Sonia that you're worthy.
As far as I can tell, Mirabella is unequivocally The Legend's worst Companion, with little to recommend her.
Narratively, I'm not very fond of her, either. There's some bits and pieces to how she's written that are sort of interesting -I do genuinely find it intriguing that she in some sense honors her betrothal to Lucky James, and yet that seems to only really boil down to 'won't marry someone else and won't deliberately harm him and his... unless he comes within thirty feet of her, anyway'. That's really about it, though. Otherwise, she's a pirate girl the player character goes 'hubba hubba' at without provocation (A rare case of the game just flat-out deciding how the player character is reacting to a person or situation) and the game sort of quietly glosses over that you're marrying a pirate ie an enemy of all mankind. Which is weird, because the game goes out of its way to make it clear that all the male, non-marriage-option pirates are crooked at best, even the relatively 'good' ones.
There's just this vibe that I'm supposed to be thrilled to get the chance to marry Mirabella, and I'm not really sure why the game thinks I would be, even aside her less-than-stellar gameplay benefits.
Gerda
+1 to Morale for allied Dwarves. (The faction type, not the specific unit)
Equipment slots: Armor, Boots, Regalia, Regalia/Shield.
This is really not the game to be specializing in Dwarves as a race, unfortunately, and +1 to Morale isn't even that great. If you want to stack on Regalia, she's not the best at that. She is completely unique in being able to wield a Shield, but wielding an extra Shield isn't that amazing -the list of Shields doesn't offer anything particularly outstanding in terms of stacking Shields. (Unless it's possible to get two copies of the Dwarf-specialized Shield, which I don't think it is) She's also unique for having Armor+Boots+Regalia, and that's notable? I guess?
In any event, she's probably better than Mirabella, and isn't really particularly later in the game, in practice. That's... something. I guess. Personally, I've never been able to justify actually using Gerda. Maybe if I was committed to doing a gimmicky run where I ran Dwarves as much as possible?
Narratively, Gerda's story is creepy, She's under-age by Dwarven standards, seems to have an appropriate mentality for being underaged, and her father's treatment of her is more-or-less abusive. She's eager to please, apparently from a lifetime of said abuse, and it just adds a layer of creepiness. I think it's meant to be creepy, thankfully, but it's hard to say. If nothing else, this is a Russian game, and my experiences with Russian-made games have involved enough cultural dissonance I'm not ready to commit to that assessment.
It's also possible Gerda's story was meant to be more developed than it is. The Legend is sufficiently polished that I didn't notice on my original playthrough, but on later playthroughs I've caught a number of little oddities suggestive of 'missing' content. For example, once you're past Darion, the density of quest-givers and the robustness of said quests drops fairly dramatically, while the number of buildings that stand out while being pure decoration climbs. (I found this particularly striking in the elflands, where there's entire 'villages' with no clickable structures and no NPCs) There's a number of other oddities of that sort centered on Kordar -such as the Giant Spider being poorly tuned as a boss fight- and Gerda's dialogue options are shockingly limited compared to the other Companions, which would be consistent with this issue.
Notably, her internal file designates her portrait with the addendum 'ugly'. While this could be the devs gratuitously being mean to an imaginary girl, the internal file designations for The Legend are extremely consistent about only attaching such qualifiers where there's some fairly obvious reason to do so. The only other Companions in The Legend to have a similar attached description for their portrait files are Feanora and Rina -to distinguish between their two forms. There's enough similarities between Gerda's story and, say, Cinderella's that I can imagine Gerda was intended to appall the player character, and then somehow be possible to turn into a more attractive and incidentally more intelligent and aware individual, and then the story could've done something to tone down the creepiness of the story at that point.
It's too bad, if so, that this didn't make it into the actual game.
Neoka
+1 to Morale for allied Elves. (Again, the faction type)
Equipment slots: Artifact, Belt/Regalia, Regalia, Regalia.
The choice for stacking Regalia like mad. Also she specializes in Elves I guess, but again, +1 to Morale just isn't that amazing in King's Bounty: The Legend. This isn't the random bonus turns of the Heroes of Might and Magic games, here.
Unfortunately, she doesn't show up until really late in the game, and The Legend's punishment for divorce involves a percentage of your current Gold being stolen, which makes it dubious to, say, take Feanora as an interim solution and switch over once you've got access to Neoka. Not heinous, but undesirable. Also you're fictionally marrying a fictional girl who you intend to fictionally divorce for your own personal convenience, you inconsiderate jerkface.
Narratively, I'm not particularly fond of Neoka. She's an Elven princess who is all wowed by you saving her from the besieging Undead forces and instantly falls in love with you who also wants to escape the oppression of being a crown princess when what she wants to do is see the world and be free as a bird, which hitching herself to you is supposed to somehow achieve. She reads like a weird intersection of stereotypical female wish fulfillment fantasy ("I'll marry a good man who rescues me from my oppressive life") and stereotypical male wish fulfillment fantasy ("Hail the conquering hero and shower him in hot babes!") and the overall end result manages to be neither all that realistically plausible (How exactly does marrying the Darion Royal Treasure Searcher let her duck out of her responsibilities as heir apparent to the Elven crown? At most this means that the player is now being inducted into Elven royalty, trapping the both of you!) nor all that satisfying a fantasy from either perspective.
It's especially strange because Neoka doesn't even really fit into the thematics of the Elven narrative stuff. One of the undertones to how the Elves are written in The Legend is that they think they're all that and a bag of chips, while the game makes it fairly obvious the player isn't meant to take them seriously. (Example: there's a Dwarf in the Elf lands who comments that the Elves won't let him smoke tobacco because it'll 'pollute the air', and complains that their druids make potions that stink so bad they literally kill birds that fly overhead. My personal favorite, though, is an Elf calling Orcs savages for using a democratic system of election instead of a lineage-based system of royalty) If Neoka is meant to be tapping fantasies about marrying into awesomeness/being so awesome everyone wants to marry you because you're just that awesome, The Legend is undermining that by making it clear the Elves are nowhere near as awesome as they think they are. In that context, marrying Neoka should logically be more like marrying some jerk with an overinflated ego who constantly reminds you of Just How Awesome I Am, Filthy Peasant, You Are Barely Worthy Of Touching Me, Let Alone Being Married To Me.
Neoka would've been a better fit if she'd been more of an actual rebel, finding her people distasteful hypocrites, or something of the sort. I'm actually surprised The Legend didn't build on the broader indications that Elves invented necromancy to run Neoka as your Undead-supporting Companion. A rebellious princess who wants to get out into the world and practice necromancy in peace would've been a lot more interesting and consistent with the overall writing of the Elves, and would've been a good moment for The Legend to be a bit clearer that practicing necromancy isn't inherently evil, even though so many undead in the story are bad guys. The game touches on this intermittently, such as the backstory of Black Unicorns being that they are the way they are from being raised in the Land of Death, where the way they are isn't evil or anything, but a lot of these examples are sufficiently subtle I both wonder how many people missed the implication and also occasionally wonder if they're actually intentional.
To be entirely fair, I suspect the team initially started from a more 'straight' intention with how they were writing the Elves, and sort of organically drifted into poking fun at stereotypical Elves instead of just writing them as stereotypical, end line, and the Companions .txt file implies Neoka was probably part of a first 'generation' of Companion ideas (She's placed strangely early in the file, given how late in the game she is), so it wouldn't surprise me if she got defined, written, and then basically not touched on while the team's concept of Elves as a whole underwent a subtle shift.
Still feels like a missed opportunity, though.
Ultimately, the main reason I have trouble justifying waiting for Neoka is...
Xeona
+1 to Morale for allied Demons. (Yet again, the faction type)
Equipment slots: Weapon, Weapon, Artifact/Belt, Boots.
... that you can get Xeona in a similar timeframe, and her equipment slot list is waaaay more useful. Weapons include many very powerful effects, and Weapons aren't really designed with the potential for you to stack so many of them at once in mind! (Which is to say Weapons are really good) If you're going to wait until the end-game for a Companion, Xeona is usually going to be more useful than Neoka.
Narratively, I'm not sure how to take Xeona. If you take her at face value, the whole thing is a wee bit uncomfortable, with her talking about how she's your slave for life and blah blah blah. On the other hand, there's another Demoness in the same area who the player can interact with fairly significantly, and she behaves similarly to Xeona (In terms of eg acting like she's a helpless, defenseless girl) while the game makes it extremely clear that this other Demoness' behavior is in large part an affectation to manipulate people. This could be meant as an indication that Xeona's own behavior is similarly disingenuous, and it's pretty clear that Demonesses are pretty much succubi that for whatever reason didn't get named that. (I'd guess 'didn't get translated that way', except I've dug around in the game's files some and it's pretty obvious that a lot of the names we get in English were, in fact, the intended English names. Otherwise there wouldn't be the occasional oddity like 'Engineer' being labeled 'Ingeneer', among other clues)
I'd actually find Xeona fairly interesting if she's effectively meant to be a succubus the player character fails to see through, who nonetheless is fairly harmless in at least the short term.
On the other hand, the Russian King's Bounty games tend to play the demons as fairly pedestrian, ordinary people, just like you or me, other than that whole 'sprawling interdimensional empire' thing. So... it's difficult to parse the intentions here...
We do get to see Xeona again in Warriors of the North, and the way she's played there is fairly notable. We see she's still got a fondness for Bill Gilbert (The Warrior is the canon protagonist of The Legend), but the whole slave-for-life thing doesn't come up and it's clear that he doesn't consume her every waking moment or something. He's just an ex she was particularly fond of, and as a Demoness she's got a lot of men in her history, so it's sort of inevitable that some will have stuck in her memory better than others, not to mention Bill Gilbert seems to have been the most recent man in her life, since she's been busy ruling over Demonis and all. I'm not sure if Warriors of the North's handling is instructive of how I should take The Legend's presentation of her (ie that she genuinely like the player character, but isn't quite as creepily devoted as she makes herself out to be) or if it's a retcon, but either way it's a bit of a relief.
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I like the (mechanical) idea of the Companion system, but The Legend's implementation is... wonky.
In terms of the mechanics, the Companion system is kind of like a sub-classing system. Xeona makes you more Warrior-like with the Weapon stacking, Feanora makes you more Mage-like (Especially in human form via the Intellect boost) with the Artifact stacking, and Neoka makes you more Paladin like with all that Regalia, as the most clear-cut examples. The equipment end of it works decently enough, and is pretty cool -if you're frustrated by your Mage's singular Regalia slot, you've got three Companions for increasing your Regalia slots, or if you want to stack a million Artifacts, than Feanora has your back. That's pretty neat, with the only caveat being that it's heavily influenced by the distribution of possible gear in the game, which both means that it's a bit opaque (What exactly are you choosing between? You'll have to consult a guide or play the game a few times and 'get a feel for it') and also means it's rather dependent on the design team's decisions made regarding gear quality.
For instance, there's only one Shield that's particularly noteworthy (The one that's +8 Defense and slashes Dwarven Leadership requirements by 20%), making Gerda's unique access to a Shield slot pretty underwhelming, while Feanora's unique access to a Helmet slot will usually be pretty lackluster, as the majority of Helmets provide minor bonuses. Whereas part of why Xeona is potentially worth waiting for is that she not only has double Weapon slots, but her other two slots cover all the overall best other equipment slots. It's pretty accurate to say she has the best setup for equipment slots of all seven Companions.
RNG also ends up playing into this: my first two runs got the Crown of Thorns within the first couple hours of play. One Impossible run never found the Crown of Thorns anywhere in the entire world. So within the context of a single run, one Companion's gear options may be really nice that normally is lackluster while one who is normally amazing is not worth it because your run just plain didn't generate the relevant stuff. Which makes the whole thing a bit frustrating, especially since it's handled as a major decision where backing out of it is possible but undesirable: you can pick up Rina at the beginning of the game and just switch over to whoever turns out best-supported by the gear you loot, but it takes a hurtful chunk of your Gold in the process, no matter how far into the game you are.
The other big mechanical issue I have with the Companions is their scaling issues. Part of the reason Rina is by far my preferred Companion is that she's the only Companion whose bonus is consistently excellent throughout the entire game, albeit army-specialized. (But then, human-form Feanora's is the only one that isn't army-specialized) For Mirabella and frog-form Feanora, their doubling of Attack eventually becomes less and less of an actual boost, due to hitting the cap on Attack's benefits as your Hero's Attack climbs while enemy Defense only gets equivalent boosts in fights against enemy Heroes. For the assorted Morale-boosters, you can have the Morale bonus be outright wasted -Neoka's Elf boost, for example, is nearly invalidated by a mono-Elf army that includes Druids and is backed by a particular set of gear whose Set effect provides +1 to Elves, as Morale only goes up to +3 and there are precious few ways for Morale to be lowered during combat. At that point she's just boosting the Druids. (Though admittedly Druids are so bad in The Legend this is a somewhat dubious example)
Feanora's human-form Intellect boost doesn't run into an equivalent cap, but it's still the case that the higher your Intellect climbs, the less important her contribution becomes.
Ideally, all the Companions would have provided unique bonuses that remain noticeable and interesting all throughout the game, and... Rina is the only one who really fits that bill.
I'm also not a fan of the placement issues. For later Companions, the game doesn't really reward you for waiting for them, and if it did that would instead tend to lead to the early Companions only being worth considering as a temporary stand-in. It's basically an untenable situation, with the only good answer being to have the Companions all clustered fairly close together, in terms of accessibility.
The placement issue takes a bit to be addressed by the series, too. Armored Princess doesn't address it at all, Warriors of the North restructures the whole into a system that has its own problems, and finally Dark Side makes a system I'm pretty much completely happy with.
On the plus side, the later games make it less creepy.
... except for Dark Side, but in its case the creepiness is intentional, so fair enough.
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As an aside, the .txt file defining the Companions in The Legend is a bit interesting to look at, as its order goes Mirabella->Neoka->Gerda->Xeona->human-form Feanora->all the children->frog-form Feanora->Rina and then Zombie Rina. This seems to imply Feanora and especially Rina were later additions, which is interesting as only Mirabella and Xeona are particularly connected to the actual main plot. (You don't have to interact with either of them, but you'll tend to end up doing so if you're just following the main plot thread) So basically they made 1 of each non-Undead and non-Neutral species/faction (Though Mirabella doesn't benefit Humans as a faction, admittedly), and only later an Undead option as well as what could be sort of viewed as a Neutral option.
Anyway, next time we'll be getting started on Armored Princess. Alternatively, if you missed it, here's a link to the Turn Order Tiers and Damage Types post for The Legend.