Preface: I wrote this post before I learned that the user The_Dawn_Will_Come reached the same primary conclusion a while ago. Still, the post I'd written contained some other connected ideas that I think could be interesting, and which help expand the theory a bit.
A fairly common pattern seen throughout the game's architecture is the quatrefoil, which some have alternatively described as a clover. Sinister Stromboli has catalogued a number of locations it's found in, including Liurnia and Raya Lucaria, Stormveil, and Farum Azula. It is also found in Elphael, and in many of the larger undestroyed churches, including the Church of the Eclipse and the Redmane Castle church. Finally, it's also present in Liurnia's Temple Quarter.
quatrefoil symbol on the stained glass window, and above the statue's head
After seeing a post that referred to the core structure of the Farum Azula Elden Ring as a clover shape, I realized the two patterns were the same. I'd recently been thinking more about this core structure, but it was the word 'clover' that more immediately stood out to me and helped me understand the congruence of the two shapes.
Farum Azula's Elden Ring
If the quatrefoil is the earlier version of the Elden Ring, it makes sense that we'd see it in Farum Azula, which contains the older Elden Ring depiction. This is some of the strongest evidence that the two symbols are meant to be associated. It's also not surprising that we find it in Stormveil, which took a number of motifs and ideas from Farum Azula.
The presence of the symbol in Raya Lucaria probably has to do with the Four Belfries, but I think the symbolism of the Four Belfries could in turn be descended from Farum Azula.
All of the locations accessed by the Belfries' waygates can be narratively connected to the Crucible in some way. Farum Azula of course has the Farum Azula Elden Ring, which has been theorized to be the Elden Ring of the Crucible age. The Precipice of Anticipation is linked to the Crucible through the Golden Lineage and Godfrey, who led the Crucible Knights. And we find one of these Crucible Knights on the other end of the last waygate, to Nokron.
There are more connections to the Crucible. The four torches at each belfry are the same kind used before the Grand Lift of Rold, which is guarded by a Black Blade Kindred and leads to the Forge of the Giants (a crucible) and Farum Azula. (These torches are also the bottom portion of the post caps in upper Leyndell, which I have written about elsewhere.) Moreover, the belfries have reliefs of the ancient dynast on them, who was probably a prophet of the Crucible. Surrounding the dynast are roots/branches, which in addition to the dynast's statues, are also found in the Farum Azula Elden Ring.
ancient dynast in one of the four belfries
Nameless Singer referred to the central structure of Farum Azula's Elden Ring as a diamond, and noticed an identical arrangement of rings on the tiles of the main connecting road in the Lands Between, which they called the Goldroad. This road has the same purpose as the Four Belfries: to connect the rest of the world to the Lands Between, and unify them. The word 'diamond' is also fitting, because the Four Belfries connect the "four corners of the Earth", and a diamond has four corners.
In some versions of the quatrefoil, like this one in Raya Lucaria, the quatrefoil is surrounded by an actual diamond.
There are some other interesting parallels between Liurnia and Farum Azula. Both are "castles in the sky": Farum Azula is literally a floating castle, and Raya Lucaria looks like one with the reduction in the water level. Both have something to do with the color blue: Liurnia has water, and Farum Azula is in the sky (Azula). Both locations are linked with the elevation of consciousness: Raya Lucaria with education and study, and Farum Azula with the evolution from beast to man. Next, if you look on the map, the bridge to Ranni's divine tower seems to point to Farum Azula. This is also true for Stormveil's divine bridge—and Stormveil of course is linked to Farum Azula in many ways. Finally, both Farum Azula and Raya Lucaria are associated with light: Farum Azula is the seat of the sun, and 'Lucaria' could be interpreted as meaning "light".
[Tangent: the ancient dynast arguably represents both causality and regression. The Four Belfries expanded the scope of the Crucible civilization through the waygates, but also probably through the infiltration of the Crucible's roots throughout the Lands Between. Expansion and growth are manifestations of Causality, as demonstrated in the Law of Causality incantation. Yet the dynast also symbolizes regression, since he is "returning to the roots". Thus, it could be said that the Crucible had the same principles as Golden Order Fundamentalism, and that it was not a purely regressive force.]
The quatrefoil's presence in Castle Sol can be explained by the culture's strong ties to Stormveil, and I think the same is true of Redmane Castle. The Redmanes imitated Godfrey in various ways, including in the architecture and symbols they used. I don't think Fort Gael would be named such (or contain lions) were it not for Stormveil's influence. As proof the castle is taking inspiration from Stormveil, you can find a stormhawk depicted on Jerren's chair, and the chair found beside the lift leading to Radahn.
chair by the lift to Radahn
All of the churches mentioned share the same stained glass windows. At the top of each window is the quatrefoil symbol which is not part of the glass, but is sitting atop and in front of it. Its placement at the top of the windows would suggest it's of great religious importance.
Edit: the fact that a very similar overlay is found in Raya Lucaria's stained glass, which has different designs in the glass itself, is counterevidence for the interpretation above. If the quatrefoil isn't surrounding a unique shape, it might not have a unique meaning. I'll include pictures of the Raya Lucaria stained glass toward the bottom of this post.
This picture is from the Redmane church. The stained glass integrates a number of aesthetics important in Elden Ring: the \"stain\" is color, and the colors are illuminated by light, which is associated with the Elden Ring, the Greater Will, etc.
Below the symbol on the left and right are two similar shapes which look more like the modern Elden Ring. Altogether this could represent how the modern Elden Ring is descended from the original, like in a family tree. Or it could be showing how the original ring is superior, since it's sort of propped up by the other two. Another idea is that it's showing the original Elden Ring as the pinnacle and yet a component of the modern ring, since the three patterns create a triangular shape, similar to the shape of the current Elden Ring itself.
Even more interesting, in my opinion, is the stained glass design framed by the quatrefoil: in the windows of the Stormveil churches, Church of the Eclipse, and Redmane Castle church, the quatrefoil surrounds a depiction of the sun. This is strong evidence that the symbol is indeed linked to the Farum Azula Elden Ring, because again, Farum Azula is the seat of the sun.
I've also speculated the quatrefoil could explain the non-aggression symbol found in these churches (on the left side of the screen) and in a few other locations, and that this symbol could also be a representation of the sun. While I don't remember every location this symbol appears in, all the examples I can think of could be linked to Stormveil or Stormveil-adjacent imagery. For example, the Roundtable Hold is based on the Fortified Manor, which uses Stormveil architecture. Another example is Pidia's church, which does not have the stained glass windows but nonetheless has the quatrefoil on the sides of the pews, and a bisected version of it on the walls.
Curiously, this room also has the same ceiling pendants as the Roundtable Hold.
Another location the quatrefoil is found in is Elphael. To put it succintly, I think the symbol is present here because the Haligtree is in many ways a return to the Crucible.
https://preview.redd.it/ljcyhg8n9j2b1.jpg?width=2560&format=pjpg&auto=webp&s=a39f1afc819cead088d9f198f0e2da0ef4a0c5a9
The quatrefoil was used in previous FromSoft titles, namely Dark Souls III and Bloodborne. In these games the pattern was also used on churches. It wasn't just this symbol either; the surrounding designs on the church doors were reused as well. However, I don't think this entails that the symbol has no unique meaning in Elden Ring. I don't believe the developers would use a symbol that matches the game's namesake (especially when the game is about symbols) unintentionally, or in contradiction.
It's possible, for example, that the Farum Azula Elden Ring was based on the preeexisting quatrefoil texture.
identical symbols on the church architecture in Bloodborne
In the picture above you can see the same pattern as in Elden Ring, with the trifoil on the lower left and right, and the quatrefoil above and between them. What I said about the quatrefoil not being used carelessly is probably even truer in the case of the trifoil, since the trifoil resembles the current Elden Ring, and is thus an even more important symbol than the Farum Azula version.
The fact that both these patterns weren't just copied, but iterated in architecturally novel ways (like in the picture below) would suggest there's not only meaning behind the trifoil and quatrefoil, but their placement and positioning to each other, as well.
quatrefoil and trifoils in Farum Azula, right outside Maliketh's room with the ancient Elden Ring
Below are the Raya Lucaria windows I mentioned earlier.
in the elevator entrance to Raya Lucaria
For the above screenshot, I'd like to point out that the quatrefoil contains blue and gold, which are two colors associated with Farum Azula. This pairing can be seen in the Bestial Sanctum, and on the beastmen. Perhaps these colors also symbolize the marriage of Radagon (gold) and Rennala (blue). The blue and gold triangles together form a larger triangle, so they could be described as "two halves making a whole".
in the Church of the Cuckoo
I have no explanation for this one (the screenshot above). This sort of makes it look like the Farum Azula Elden Ring is being made subservient to a different order entirely, since now the quatrefoils are below and a new design (though related) is on top.
Endnotes on related symbols: I'm thinking that the symbol below could be a representation of the six equally sized great runes in the current Elden Ring—so excluding the Great Rune of the Unborn. I guess that doesn't make a lot of sense for Raya Lucaria, since this is where we obtain the Great Rune of the Unborn, but then again, Rennala probably received the amber egg long after Raya Lucaria was built. Another possibility is that the pattern symbolizes the six divine towers.
from the elevator entrance to Raya Lucaria
This pattern can be found in the outdoor sections within Raya Lucaria.
Likewise, the symbol in the picture above could potentially be a representation of all eight usable great runes. If you continue the pattern all the way around the missing half of the circle, I believe you'd end up with an octofoil. However, I should note this same pattern is found in Elphael, which might be counterevidence for this view. I say this because Miquella clearly wants a change to the current order; so if the current order has eight usable great runes, it wouldn't make sense for him to depict these in Elphael.
For the sake of comprehensiveness, I've included a picture from inside the church at the Night's Sacred Ground in Nokron. The floor has a pattern that sort of resembles the quatrefoil shown in the pictures above.
church in Night's Sacred Ground
Updates (5/31/23): After thinking some more about it, I realized how interesting it would be for the Elden Ring to be based on the preexisting quatrefoils, because it would mean FromSoft took religious inspiration from their own creations. This could tie into miirshroom's idea that the game Elden Ring is a crucible containing elements from FromSoft's previous works.
If Elden Ring is about taking things from the past and putting them together, and the emergence of the present and future from the past, it would be perfectly in keeping with this for the developers to look at their earlier works for symbols, and use those symbols as the template on which to grow (or graft) Elden Ring. So I think that not only was the reuse of assets intentional when designing the Elden Ring, it's arguably a demonstration of the game's core idea.
The same could be said of Elden Ring's other reuse of assets. Every reused animation could be justified as relating back to the game's themes of emergence and convergence.
On the the second Raya Lucaria window: the design at the top should logically have something to do with the Primeval Current, since as I've recently written about, the Church of the Cuckoo is used to show devotion to it. Maybe the symbol could be a depicting a graven mass? The pattern kind of looks like four simplistic humanoid figures (just their head and torso) pointing up, right, left and down, like a bunch of sorcerers grafted together.
Links:
-Thumbnail: https://imgur.com/a/XwiPbnc
-The_Dawn_Will_Come's comment on the quatrefoil, on Jygglewag's post which pulls out the quatrefoil from the Farum Azula Elden Ring (called "I broke down Farum Azula's elden ring so we can discuss it in detail"): https://www.reddit.com/EldenRingLoreTalk/comments/yyrqc1/comment/iwwfef6/?utm_source=share&utm_medium=web2x&context=3
-My first post on the torches at the Four Belfries and Grand Lift of Rold: https://www.reddit.com/EldenRingLoreTalk/comments/11b1txs/counterfire_symbolism_in_leyndell_fake_candles/

I just completed my first RL1 run of Elden Ring with no summons/spirit ashes, killing all remembrance bosses. It was only my second time playing through the game - I am nothing special at ER but have beaten all Fromsoft titles. All told, I had a ton of fun, and any Elden Ring fan who enjoys the masochism should give a run like this a try.
I was constantly utilizing this sub, Fextra, and YT for strategies - for me, researching builds, weapons, and talismans and then questing for them is a key part of the fun. As a massive thanks to everyone posting useful info and clips this sub, I wanted to pay it forward and aggregate everything that worked for me in terms of strategy, going boss by boss, with some video replays. If you want a blueprint to efficiently beat RL1, then look no further.

Starting out

I immediately got the Greatsword in Caelid, then followed the beginning of this Youtube tutorial to level it as much as I could. Shoutout u/Wargasm_Actual for his RL1 videos. I'm on console so I didn't do any skips or zipglitches.
To use the Greatsword, you also need to pick up Radagon's Soreseal, the Starscourge Heirloom, and the StrengthKnot Crystal Tear for your Physick. This will allow you to two-hand the Greatsword for 3 minutes - plenty of time to go to work on most all early bosses.
Next I went to Fort Gael and killed the Lion Guardian to get the AoW Lion Claw - this weapon/AoW combo absolutely crushes shit, it does 30 poise damage and I used it pretty much exclusively through the beginning of the game. I recommend using Fextralife to hunt smithing stone locations and level it as much as you can, at every point in the game. This means questing for Dectus medallion, unlocking Altus Plateau early, etc.
Speaking of, this run can basically be split into 2 talismans: Ritual Shield (receive greatly reduced damage at full health, for when you're trash early) and Red-Feathered Branchsword (for when the bosses start one-shotting consistently and you need the bonus damage). I had Radagon's Soreseal + one of these two talismans equipped for 99% of the run.

Early bosses

Margit - my Greatsword was +8 when I got to this fight, so each Lion Claw was hitting him for huge chunks of health. He has 80 poise, so 3 Lion Claws is an easy stagger.
Godrick - when he started his animation to transform into phase 2, I was able to get him with 2 Lion Claws for a decent chunk of extra damage. Video: https://www.xbox.com/play/media/7HFCHEZCPW
Rennala - I'd leveled up with Greatsword even further, so you'll see Lion Claw is doing massive damage in both phases. Video: https://www.xbox.com/play/media/P8KQDQTHYM
I shamelessly did the poison mist cheese on the Drac Tree Sentinel to get access to the Capital. Go get the Omensmirk Mask - this allows you to two-hand the Greatsword without needing to drink your Physick, which is a huge quality of life improvement.
Goldfrey - once I was in the Capital, I also went and got the Ritual Shield talisman right away. I kind of regret this, I should have focused on learning the movesets, as this is such a fun boss to dance with. Instead, I won this one in a really sloppy style - you can see me getting smashed in the prior attempt in my replay video: https://www.xbox.com/en-US/play/media/EZZYPKCWEP.
Morgott - I shackled this mofo hard. Combined with Lion Claw, I was able to make instant work of his phase 1 by shackling him at the start, using LC twice, then taking the crit, then immediately shackling him again and repeating. Scripting phase 1 like this made the entire fight a cinch: https://www.xbox.com/play/media/WHVZPJ7LXJ

No hit bosses

From here on out, I always used the Red-Feathered Branchsword in boss fights. Most boss attacks were killing me in one hit even with the shield talisman, and the bonus damage from RFB makes each fight go ~20% faster. This means each boss fight becomes a no hit, time to sack up.
Fire Giant - one of the tougher bosses, because of the transition I just mentioned and because he has so much health. However, I was able to mostly script phase 1 - 3 Lion Claws and one R1 is a stagger (see this at :30 in the Phase 1 video). Then ride to the next spot, 2 more LCs and you're in Phase 2:https://www.xbox.com/en-US/play/media/MT34DXDJVNPhase 2 is definitely more annoying but I recommend attacking his hands at the beginning, then riding to behind his thighs and safely attacking him from there until he rolls away. This strat eventually got me the W, but not before taking this excruciating L: https://www.xbox.com/play/media/LHQ4E8KMUL
Godskin Duo - it's all about sleep pots with these guys. Crafting these requires Trina's Lily, and there are a finite number of these in the world, so heed what I'm about to say: DO NOT TARGET THE SKINNY GODSKIN WHEN YOU THROW SLEEP POTS AT HIM. He has a fast dodge and will easily avoid. I wasted so many Lilies doing that... Throw them at his feet and bait him to walk into the cloud. Ideally get both Godskins asleep next to each other this way, right at the start of the fight. Beyond that, I quested in Volcano Manor for the AoW Royal Knight's Resolve which massively boosts one attack - with the massive Greatsword hitbox, you can really crush their HP while they're both asleep next to each other (example where I died: https://www.xbox.com/play/media/SZ98VVTNES). Ironically you have to fight the fat Godskin 1v1 to get that Ash of War, but it's good practice and worth it. Video beating the Duo: https://www.xbox.com/play/media/WCXQ56KPKP
Maliketh - the first fight that forced me to rethink my strategy of simply Greatswording everything in my path. After tons of failed attempts at getting past phase 1, I saw someone here say to try Glintblade Phalanx. Both phases only have 80 poise, so 8 glintblades is enough to stagger. This was the key to getting past phase 1 consistently - I put it on a rapier, then after the stagger I would switch to Greatsword for a crit, followed by a Lion Claw. Repeat once more and that's phase 1 dusted: https://www.xbox.com/play/media/Q7XL689MSL. Phase 2, same strategy, but since it's generally safest to stay somewhat close, I ended up just running into Maliketh with the glintblades. It took a ton of attempts but finally got him: https://www.xbox.com/play/media/SBE727LJTE
Rykard - randomly I beat Rykard as I was questing for Blasphemous Claw (which I didn't end up using against Maliketh). I just leveled up the Serpent Spear to +10 and smashed him with it, nothing too fancy, there's no shortcut. Sprint to the right when he starts the annoying earthshatter animation and you can avoid it with a roll.
Sir Gideon - he started out absolutely dicking on me, particularly with the golden rings attack - complete bullshit for RL1 melee characters. So for the first time, I went with a completely different look, using the incantation Frenzied Burst with the Frenzied Flame Seal. It requires 22 Faith, so I used Marika's Soreseal, the Two Fingers Heirloom and the Greathood (I should've just gotten the Faith-Knot Tear instead of questing through the Haligtree, not sure why I didn't). Also I didn't use Red-Feather Branchsword, not sure why. It felt great to turn the magical tables from a very safe distance: https://www.xbox.com/en-US/play/media/HBFYMS7YQ8
Godfrey/Hoarah Loux - again I struggled in phase 2, so I decided to try out the AoW Ice Spear on a Short Spear, after seeing someone on here use it to great effect. He's super fun to get nailed down, and perfectly timing dodges on his exaggerated animations is super satisfying. The frostbite proc at the end to get the lucky kill...whatever gets it done: https://www.xbox.com/play/media/DLY9CGRBRN
Radagon/Elden Beast - I found a random post on here that said he had figured out how to script the Radagon fight entirely. What a gamechanger! Double Flame Art Pickaxes +25, both with Cragblade, Raptors Black Feathers, Claw Talisman for massive jump attack damage. You can stagger him from the start and it's game over from there. There's only one tricky dodge, the stomp after he gets up - just back up slightly as he winds up, then roll into him. This is as foolproof as RL1 gets: https://www.xbox.com/play/media/SSGMUECUB7. As for EB, I was able to consistently staggecrit him. You'll see at the end of my winning attempt that he's just firing off Elden Stars..got so lucky with this one: https://www.xbox.com/en-US/play/media/AS2NSSPPCV
That's it right? I'm an RL1 Elden Lord! Well, my boys said if you don't beat Malenia, it's not a real run. Fair enough... I decided to go for the rest of the Remembrance Bosses.

Clean up

Loretta - I used Ice Spear again. https://www.xbox.com/play/media/XX629LCS3B
Malenia - here I have to shout out u/gilfordtan. This guy is a total lunatic, I highly recommend checking out his Youtube channel where he's consistently stomping Malenia (and every other boss) with about every build you can think of. Criminally underrated channel, everyone should subscribe.
He recommended using the AoW Storm Blade, on Uchigatana, so that you can keep your distance while still learning her moveset. Long story short, this is the strategy that got me the W. Keep her at medium distance, then spam Storm Blade twice - she will consistently dodge the first, then charge you and get hit by the second: https://www.xbox.com/en-US/play/media/H6AH6LYVLA It's very repeatable and made the fight feel winnable. Learn how to dodge waterfowl of course. I got lucky that she did Scarlet Aeonia attack twice: https://www.xbox.com/en-US/play/media/BC3QJATFB5.
Again shout out to u/gilfordtan, you shouldn't watch me. Storm Blade turns your Uchigatana into a rifle, it's stupid strong and I would've used it a lot more in the run had I discovered it earlier.
Regal Ancestor - used the same Uchigatana + Storm Blade build.
Astel - went back to double Cragblade pickaxe + jump attack combo. Got lucky with the double hitbox proc on the first hit for monster damage. https://www.xbox.com/en-US/play/media/HX2NVPJ5B5
Dragonlord Placidusax - ditto, 2x pickaxe. In between phase 1 and 2 there is a window to reup your Cragblades on both, make sure to take advantage. https://www.xbox.com/en-US/play/media/8N6B5N3NAG
Valiant Gargoyles - Uchigatana + Storm Blade absolutely crushed them, huge HP chunks with each hit. https://www.xbox.com/en-US/play/media/ZJVTFZUVH8
Lichdragon Fortissax - I returned to the Frenzied Burst build from earlier. He's stupid easy from range, just stay away from him and be moderately conservative, I think this took me 2 tries. https://www.xbox.com/play/media/N3CRX6793Q
Mohg - for my last boss, I was glad to utilize Mohg's Shackle, which like Margit's can slam him twice in Phase 1. He's weak to bleed, so I brought back the 2x pickaxes w/ Bleed Cragblade and the jump attack combo. Back off and stop damaging him around 60% health, during the first two curses "Tres" and "Duo" then he will reengage in combat. I was able to shackle a second time and rack up some crazy damage with consecutive jump attacks. Basically avoided Phase 2 altogether, beat him in under a minute. https://www.xbox.com/play/media/EBAXNN5TSH

Conclusions

Elden Ring is an incredible game, and RL1 brought a new dimension to the gameplay that was incredibly addicting and rewarding. The intense rush from beating each boss is wild.
I encourage any casual Elden Ring fan to give RL1 a try - there are tons of tools and tricks that make it super achievable without godlike skills. Forgive my massive wall of text - I got so much out of this sub, and I wanted to organize everything that worked for my run, in case it's helpful to anyone else.
https://preview.redd.it/h1xcnzfxnesa1.jpg?width=1920&format=pjpg&auto=webp&s=a3663f11d5f09e420cf7ee7497b78241a3b94b7d