(Alright third time's a charm)
Megaliths are one of my favorite archetypes in this game because the concept of a ritual archetype with only ritual monsters is the kind of innovation that makes this game fun. They are also extremely cheap, you can pick up a full megalith core for under 20$ and you can easily get this deck down to 150$ or less by cutting the expensive extra deck monsters like Zeus and Accesscode. They are nice to have, but not mandatory by any means. Also you can nuke your opponent on their turn which is just sick.
Card Breakdown
3 Megalith Phul - This is the single best card in the entire archetype. It does literally everything you can want a card to do within reason. It recurs a ritual monster on summon to lessen the impact of the card deficits that are inherent in ritual summoning while also modulating its level for XYZ plays. Its second effect is even better, allowing you to ritual summon a monster from the deck at spell speed 2. This is insane. You get to special summon a monster from the deck, which is one of the strongest things you can do in this game because it is both searching and field presence, and it being spell speed 2 allows you to bring out Megalith Bethor on your opponent's turn to pseudo-nuke them in the middle of their combo. This guy is both your starter and your ender in most of the 2-3 card megalith combos and it carries the entire archetype on its back.
3 Megalith Ophiel - Ophiel mostly facilitates consistency by searching a Megaltih (usually Phul, but sometimes hagith) and then using itself as the material to summon them. Its also useful in a few combos where you could already search a megalith but using Ophiel as a middleman will make the end result better, usually by giving you an extra Bethor pop or Letting you use Phul's on summon effect to make it level 4.
3 Megalith Hagith - Hagith is the megalith backrow searcher, and while there isnt much of it, its still good enough to be worth searching. You can run 2 Hagith but from my experience you are pretty happy to see this in your opener so its worth the third copy.
2 Megalith Bethor - Bethor is the biggest playmaker Megaliths have. It essentially field nukes your opponent on summon which is always a welcome effect in any deck. It can brick your hands though because it relies on the other megaliths to set it up, so running 3 is not advised.
2 Megalith Aratron - Aratron used to be one of the best cards in the deck because of the hand trap ritual summon but since the block dragon ban finding the resources to use it effectively has become significantly harder. Its still worth playing because it offers solid protection and recycling for your other Megaliths and the spell speed 2 ritual summon can save you in a pinch, but its not the staple it used to be.
3 Manju of the Ten Thousand Hands - Megaliths don't have a normal summon in their archetype so playing ritual monster stratos is a great boost to consistency and being level 4 makes it useful for XYZ plays with Phul.
3 Senju of the Thousand Hands - Megaliths don't have any ritual spells so Senju is effectively identical to Manju and its worth playing for the same reasons.
8 hand traps - I'm going to break my own unofficial rules here and just say you can run any 8 hand traps by preference. Outside of Nibiru which is risky to run maindeck none of the hand traps have that much synergy with Megaliths so just play whatever.
3 Megalith Unformed - The first effect of Unformed is barely ever relevant but that doesn't matter because the second effect boosts consistency and allows you to start your plays without a level 8 Megalith. Its also an important part of the decks best combos.
3 Dark Ruler No More - It breaks boards going second like nothing else and this deck can't really afford to discard for things like Forbidden Droplet or Super Polymerization. Run this or get steamrolled by Drytron :/
3 Pot of Desires - You only have 2 one-of engine pieces so 3 desires is a no-brainer.
2 Cosmic Cyclone - Cyclone is mostly here to out annoying floodgates like There Can Be Only One and -ugh- Mystic Mine.
1 Treacherous Trap hole - This is for Rafflesia, as a pro tip don't XYZ summon Rafflesia until after you activate Pot of Desires and confirm that this isn't banished.
1 Megalith Emergence - This is what you usually search off Hagith because you can use Emergence to summon a Phul from grave which can use its effect to summon Bethor to nuke your opponent at spell speed 2. After that it gives you a solid grind game.
Extra Deck
1 Abyss dweller - Its a good floodgate XYZ monster to end your combos on.
1 Castel the Skyblaster Musketeer - Its Castel, this deck can make a rank 4. This bird person was a knightmare before knightmares were a thing.
1 Traptrix Rafflesia - Another rank 4 option to end on, popping 2 cards by sending Treacherous Trap Hole is a very strong disruption but if you can already make a spell speed 2 Bethor it can be a little redundant.
1 Baguska, the Terribly Tired Tapir - The ultimate stalling tactic for rank 4 decks everywhere. If your opponent is winning, make baguska and try to topdeck DRNM.
1 Gallant Granite - Usually not as good as the other rank 4s but its nice to have around because the search can unclog you draws, with megaliths needing at least 2 card to do anything and all that.
1 Number 97: Draglubion - Megaliths can also make rank 8 somewhat easily which makes a Draglubion engine pretty good here as a negate and beatstick or as an otk.
1 Number 100: Numeron Dragon - For Draglubion.
1 Number 38: Hope Harbinger Dragon Titanic Galaxy - For Draglubion.
1 Divine Arsenal AA-ZEUS - Sky Thunder - Its zeus in a deck that can make XYZ monsters. It can be a bit redundant with Bethor, But again, its Zeus.
1 Knightmare Phoenix - Its a knightmare.
1 I:P Masquerena - I had some extra deck space free so i just threw this in because we are playing knightmares. You almost never make it but its there.
1 Black Luster Soldier - Soldier of Chaos - Its really funny to just slam this absolute beast down on someone who forgot to put a dragoon out in their deck and watch them lose.
1 Knightmare Unicorn - Okay i should probably explain why extra deck monsters with removal effects are so good for the sake of clarity and newer players. Having an answer to your opponent's most threatening cards in the forever accessible extra deck completely removes the luck aspect from whether you can remove things, which is a pretty big deal because then you don't have to play cards like Raigeki so that you have access to removal.
1 Accesscode talker - Having accesscode in your extra deck means you can always generate a ton of damage to otk your opponent and that's why its 100+ dollars and played in basically everything.
1 Apollousa, Bow of the Goddess - Its the best link monster that has the word negate on it, and while again its usually better to just make an XYZ, having it doesn't hurt.
Basic Combos
Phul + Manju/Senju
NS Manju/Senju
Manju/Senju summon ef search a level 8
Level 8 hand ef tributing Manju/Senju to summon Phul
Phul 1st ef add the level 8 back to hand
Phul 2nd ef tributing itself to summon Ophiel from deck
Ophiel ef search Hagith
Ophiel ritual summon ef tributing itself to summon Hagith
Hagith ef search Emergence
Set Emergence
On your opponent's turn, activate emergence summoning Phul from GY
Phul ef tributing the level 8 in hand summons Bethor with 2 pops, or more if you tribute hagith and/or phul from the field even though you dont have to
A level 8 and a level 4 megalith work in place of Manju/Senju
Activate level 8, tributing level 4 to summon Phul
Phul ef add the level 8 back to hand
The combo is the same from there
Unformed + any megalith except Phul
Unformed tributing the megalith to summon Phul if it is level 4 and Ophiel which searches Phul then tributes itself to summon Phul if its level 8
Phul 1st ef return a level 4 Megalith to hand
Phul 2nd ef tributing the level 4 to summon Ophiel into Hagith if the original Megalith was level 4 or straight into Hagith if it was level 8
Hagith ef add Emergence
Overlay Hagith and Phul to summon Abyss Dweller or Traptrix Rafflesia
Set Emergence
Opponents turn
After you activate XYZ monster's ef detaching Phul
Activate Emergence
Summon Phul from GY
if you have materials in hand to use Phul's effect summoning Bethor you can do so with 2-4 pops depending on the level of the original Megalith and how many materials you have in hand
Unformed + Manju/Senju
NS Manju/Senju
Manju/Senju ef search Ophiel
Unformed tributing Ophiel to summon Phul
Phul 1st ef add Ophiel back to hand
Phul 2nd ef tributing Ophiel to summon Hagith
Hagith ef add Emergence
Overlay Hagith and Manju/Senju for Abyss Dweller or Traptrix Rafflesia
Set Emergence
On opponent's turn
Activate Emergence summoning Ophiel
Phul 2nd ef tributing itself and Ophiel to summon bethor with 2 pops, or 3 if your XYZ monster has already detatched Hagith to activate its effect
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