This guide is just here for people who really like a challenge. I can't fraps because I run on an laptop which already struggles when either boss breaks pillars. Therefore I don't have proof that I've done this, but hopefully nobody cares.
Besides, doing this without a video tutorial makes it more interesting for those who really want a challenge :)
There's only one real secret to soloing Nightmare at the Ruins which is pretty much already known and that is that you really need to separate the bosses to make the battle 2 separate fights. This is extremely difficult to achieve solo however, and here's how.
When the battle starts you must sprint towards Lag's right leg and tap it with your sword, stander cancel and then sprint towards 2 o'clock corner. About two seconds later Red will do a belly flop on you which can be sprint shield dodged or heavy standered. Either way is fine but sprint dodging is ideal as you must throw a Light of Palala immediately after and start running back towards 7 o'clock corner while they're blinded. *Credit to Hazard for showing me this*
From there Green should aggro you, but it can also be Red too. If done properly you will only be fighting one spider.
If you fail to do this at the beginning you can salvage by luring them back, but it is obviously much less clean.
Fighting the spiders solo is really all that's needed to know from here.
I highly recommend using heavy shield for this because although there are counter opportunities, standering with a small shield has so much knockback that there is the imminent threat that you'll aggro the second spider if not spaced properly.
Red has 6 distinct attacks.
1 Jump: Red rears back and leaps forward with a massive hitbox surrounding him entirely. This is a smash attack, and recovery time is medicore. You can get a few sprint slams or a bamboo splitter after, and even a blossom blow depending on his followup (180* is common and you can get in blossom into stander)
2 180* Swipe: Red rears his right claw and sweeps his left side approx. 180*. He will generally only use this when you're to his side, it is a smash and has mediocre recovery. You can get in a bamboo splitter after standering with heavy shield. Sprint slam is doable with normal shield but watch your stamina carefully.
3 2 Hit Smash: A very obvious smash that begins with Red rearing his right claw and then smashing with his right followed by his left. With regular shield the second swing will miss 90% of the time, but I'm not entirely sure about the conditions for this, it seems in corners you may be more likely to get hit. With heavy shield when you stander the first strike immediately let go of stander and do a blossom blow *Edit* (if you let go immediately you risk taking the second hit if you misjudge, you can still get in 1 hit blossom blow if you let go after second swipe but only if it whiffs), you will sometimes be able to get in two hits of the blossom if you recognize his next incoming attack as a slow one (180* is most common followup). THIS WILL ONLY WORK AT POINT BLANK RANGE. If you are at any distance when he begins rearing his right claw stander guard both hits and do a bamboo splitter.
4 Quick Strike: This is a very quick non-smash strike with Reds right claw with almost no visible tell. For counter soloing this is the easiest strike to perfect guard as it comes out very quickly and is extremely reaction dependent. Heavy shield users have time to bamboo splitter after guard, but you must stander cancel and if he quick strikes again, you have to stay in stander (I have not successfully stander canceled into a perfect guard of a second Quick Strike).
5 Slow Strike: This is the most obvious attack Red has, he rears back on his left side and attacks a second later with his left claw. This attack is counterable and when perfect guarded can be followed up with a Butterfly Swing. Unfortunately for large shield the perfect guard technique doesn't work, you can only go for bamboo splitter safely or risk going for blossom blow after a perfect guard OR...you can stander underneath the attack entirely but this is much more consistent on Green. Following a “ducked strike†you can safely bamboo splitter, or go for blossom and stander in time to block almost any incoming attack (haven't had any issues with any of the attacks yet).
6 Dual Claw Swipe: This is his rarest attack, he puts his two claws together like they're fangs and rears them to HIS left, then spins about 180* to his right. It is a smash attack with a decent amount of recovery so feel free to blossom blow.
Laghodessa:
Laghodessa has 2 additional attacks and has one major difference in Jump.
1 Spit: Straightforward spit smash attack that doesn't do much damage but puts a massively painful dot on. She likes to do these consecutively as well for some reason. There’s almost no recovery for her on this so just block.
2 Butt Slamming: This attack has no real tell, but will only be done if you're at her back. She smashes the ground up and down a number of times with her thorax (note: it hits the ground right and left alternating). This attack has a surprisingly small hitbox and therefore you can wind up an entire amaranth kick while she does this if you notice it coming. She also likes to do these consecutively if you stay at her back so you can bait them for a free blossom blow or amaranth.
3 Jump: Her jump now has a painful follow up slam. Normal shielders can double stander for massive stamina eaten. Heavy shielders can double stander or just sit in stander. I believe it’s doable to shield slam out of the radius (it often whiffs anyways depending on the angle) but I don't think it'd be worth it. The follow up is extremely slow, but scary so I suggest just waiting it out unless you’re good enough to recognize you won’t get hit.
*Edit* Green may opt not to do the second slash after Jump, but I have not figured out any tell for it, you can definitely recognize though if she IS going to do it and assume not otherwise, but it's riskier to assume not.
This battle is really only about being able to solo each spider individually and being able to execute the palala flash entrance. It's frustrating to attempt, but very rewarding if accomplished.
The most important thing about soloing these spiders, and I can't stress it enough is to WATCH YOUR STAMINA. If you're ever below 20 stamina I highly recommend NOT going for your additional hits between attacks and using the time to recover that stamina
Another MAJOR factor in this battle is positioning and spacing. Getting cornered is extremely dangerous only because you cannot read the spiders attacks in the corner. IF you get cornered, you really can only try your best to find a way around while defending yourself with yomi (guessing the spiders next attack). Basically at all times be aware of your surroundings and do your best not to get pinned in a corner, and obviously keep the spider close to 7 o'clock corner while the other one is waiting for you. It's definitely tricky to lure the spider to the corner and keep him there without cornering yourself, but it is of utmost importance.
Spacing is essential in knowing when to attack and what attacks to use. I mentioned if you're not point blank for 2 Hit Smash you need to heavy stander both attacks. This consideration goes for all attacks. Sometimes you'll be out of range of jump and you can wind up an amaranth. Sometimes when you duck under his Slow Strike you'll be in great position to start a blossom blow because he takes so long to return to face you, and his only other real option is 180* Swipe. These considerations you will learn over time, and will be able to do this run faster and faster. This may seem obvious to many of you but it is really one of the biggest factors in the entire game.
Also any place where I mentioned bamboo splitter being possible, you can also shield slam to get either spider down. Shield repair becomes necessary after campfire buff wears off, and should only be used after a standered Jump, or if you're out of range of any of the long recovery strikes (180*, 2 Hit, and Butt Slam).
For people just beginning I recommend only going for bamboo splitters at all openings and then when you learn the attacks and timing you can be more bold.
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If anyone has anything to add or correct (I'm writing from memory mostly) please feel free.
For those of you who wanna call bull**** on me feel free I don't mind.
Anyone who succeeds and CAN record a video I'd LOVE to see it! Especially if you figure out any smarter strategies.
So far I've completed Nightmare at the Ruins on NORMAL mode without any oaths, without using any cash shop items ie Goddess Grace or Mercenary Potions.
I will be attempting harder difficulties in the future and if I get access to a capable computer will attempt to record a run and post it here.
Thanks for reading!
*Edit* Just soloed on Hard without Macha in approx 20 minutes. Sloppy run though I Shield Repaired with 12 stam and couldn't roll cancel, that cost me about 500 HP.
I'll try to make a Small Shield guide next, Heavy Shield seems to make this fight rather easy once learned.
Hard Macha done in approx. same time. *Edit* was actually closer to 25 minutes on hard macha (being too safe)
http://www.youtube.com/watch?v=VPH4TNFmH9U this is a video of me 2 manning with my Evie friend Hazard. This is from her perspective because I can't record, but soloing is basically the same deal, you just need to use more shield repair, and be more careful about the corners, and obviously do damage much much slower.
http://www.youtube.com/watch?v=8jJNsPLoHZI new 2 man video. This time with another Evie friend Jigalina. This time I'm using large shield which I've decided is much better for this fight overall because you get in far more attacks (a Bamboo Splitter for each of his attacks plus Blossom Blow after 2 Hit Smash). With small shield you're eating so much more stamina and getting knocked back after every smash, the counter's as a trade off aren't worth it. Also this time was done with no Palala's and no corner glitch. The video itself is much more of an Evie solo on Red unfortunately, I really need a new comp to record.
*UPDATE* Soloing this with a small shield is infinitely harder in every way. Spacing is harder because of knockback, stamina management is harder because standering eats 50% with small shield on most of her smashes, and last but not least when you hit 0 stamina on large shield from blocking you're NOT fatigued, with small you are...guaranteed free hit for either spider almost always.
Here's what to watch out for, when Lag does Jump and does the followup this will eat almost your entire stamina bar. She does this multiple times very often when you use small shield because you get knocked back to the distance she likes. I'm working out the possibility that the followup can be consistently dodged.
I have yet to complete this mission solo on Hard Macha with a small shield, I have come close to downing Laghodessa only to be cornered at the worst possible times.