Yu-Gi-Oh! Master Duel Guide to Mermail/Atlanteans

Introduction

This won't really be a guide to all of the cards like I usually try to do (because that would take way too long), but instead I'll basically mostly be explaining cards in the deck list I've provided, to keep it simple and sweet.

Now, what does this deck aim to do and why should you choose it?

Firstly, the deck aims to discard WATER monsters in order to gain benefits, not unlike Dangers! Some of the Mermails have effects to discard in order to special summon themselves, some have effects when they're sent to the GY or discarded, and some can discard themselves to activate effects. Atlanteans, on the other hand, help get the ball rolling, allowing you to get a lot of hand advantage (more on that after this).

Why should you choose it? It's a fun deck to pilot, also allowing you to swerve around floodgates you might see (though that's probably less of a worry now after some being limited). I wouldn't really recommend this during the current Tear format, but give it a go if you want to.

Deck List

Feel free to suggest changes or tech options.

Main Deck Monsters

Mermails:

Mermail Abyssgunde - Abyssgunde is a card you'll want regardless, since it doesn't need to be discarded to activate a Water monster's effect (like the others do). If she's discarded, you can special summon a Mermail in your GY and Special Summon it, making her great for extending and getting your plays off. [Level 3] [2 copies]

Mermail Abysspike - Abysspike isn't all that important, but he can be used as a Normal Summon in order to get your plays started, you won't really be using him all that much. [Level 4] [1 copy]

Mermail Abyssmegalo - One of the more important monsters in this deck list, a beater that's extremely easy to summon and can search out 'the out' to pesky spells like Lightning Storm or Raigeki. You can discard 2 other Water monsters to Special Summon him, which usually can get you some searches or extend your plays, plus he's able to tribute (for cost) an attack position WATER monster in order to gain a second attack during the battle phase, useful for OTK'ing. [Level 7] [2 copies]

Mermail Abyssteus - Not quite as "costly" as Abyssmegalo, requiring you to only discard 1 Water monster in order to Special Summon, he's a searcher than can search out either Abysspike or Abyssgunde to get your plays going. [Level 7] [3 copies]

Atlanteans:

Neptabyss, the Atlantean Prince - An important piece of the puzzle, an amazing extender and combo starter. He sends 1 Water monster from your deck to the GY (as cost), to add 1 "Atlantean" card from deck to hand. This alone will pretty much start your entire combo. If he's sent to the GY (in order to activate a Water monsters effect), you can Special Summon 1 "Atlantean" monster from your GY. [Level 1] [3 copies]

Atlantean Heavy Infantry - Heavy Infantry is a must-include, if not only for helping to destroy floodgates or problematic cards. When he's summoned, you gain an extra Normal Summon (1 Level 4 or lower "Sea-Serpent"), and if he's sent to the GY (in order to activate a Water monster's effect) you can pop 1 face-up card your opponent controls (this does target). [Level 2] [3 copies]

Atlantean Dragoons- Arguably one of the best cards in the entire deck list, the searcher other decks wish they had an equivalent to. If it's sent to the GY (in order to activate a Water monster's effect) you can add 1 Sea-Serpent from your deck to your hand. The searching isn't a once-per-turn effect, making it an important piece to the puzzle. [Level 4] [3 copies]

Generics:

Deep Sea Diva - Pretty much an auto-include at 3, the deck is much weaker without her. When she's Normal Summoned you can Special Summon 1 level 3 or lower "Sea-Serpent" from your deck, which depending on your hand can, at the worst, start you off at 3 materials + searchers. She's also a tuner, allowing for some easy synchro plays. [Level 2] [3 copies] [Tuner]

Swap Frog - We'll get more onto Swap Frog's utility later, but know that even without Toadally Awesome, the frog engine is, without a doubt, a good inclusion in the deck list. You can discard 1 Water monster (this will not proc most of the discard effects, outside of Abyssgunde) in order to Special Summon him, then you can send 1 level 2 or lower Aqua monster from your deck to the GY (in most cases, Ronintoadin). More on his 3rd effect later. [Level 2] [3 copies]

Ronintoadin - Ronintoadin is very straightforward, if it's in your GY, you can banish 1 other 'Frog' monster in order to special summon it (not a once per turn), making it useful for extending. [Level 2] [1 copy]

Cartorhyn the Hidden Gem of the Seafront - The only real purpose it serves in this deck list is to gain an additional normal summon, helpful in cases your Normal Summon was negated. [Level 2] [1 copy]

Deep Sea Minstrel - Deep Sea Minstrel is mostly useful for getting hand knowledge and stopping potential problem cards, you can discard it and 1 other Water monster in order to look at your hand and banish 1 card from it. if she's special summoned you can send the top 3 cards of your deck to the GY (which will proc effects usually) and place 1 card from your GY on the top of your deck, which will usually be Dragoons. [Level 3] [1 copy] [Tuner]

Lappis Dragon - Lappis is basically here to be free material, it's a level 5 Tuner that special summons itself if you draw into it (which means it will be a garnet in your opening hand), Dragoons can search this, so even if your opponent negates Neptabyss, you can go into a level 6 Synchro at worst. [Level 5] [1 copy] [Tuner]

Moulinglacia the Elemental Lord - Moulinglacia is a hit or miss, in the current format (Ishizu Tears) you're better off not playing him (I'll suggest other cards), but if you have exactly 5 water monsters in your GY, you can Special Summon it and discard 2 random cards out of your opponent's hand. If he leaves the field you skip your next battle phase, so use wisely if you do. [Level 8] [1 copy]

Extra Deck Monsters

[NOTE: I won't be going over staple or commonly played cards]

Herald of the Arc Light - A walking floodgate that you can make with the bare minimum, Deep Sea Diva and Heavy Infantry. Any monster sent to the GY is banished instead and acts as an omni-negate. [Level 4]

Coral Dragon - A must-include, easy to make, can pop 1 card your opponent controls, can proc discard effects, and if it's sent to the GY, can draw you 1 card. It's the full package. [Level 6] [Tuner]

Mermail Abyssgaios - Weirdly enough, he's a floodgate, one that can potentially hurt you as well, since level 5 or higher monsters can't attack. Once per turn (quick-effect) you can detach a material, negate all effects of face-up monsters your opponent currently controls that have less ATK than it (he stands at 2800 ATK base, which goes to 3600 if you have Aybss-Scale attached to him. [Rank 7]

Mermail Abyssalacia - Monsters her link arrows point to gain 500 ATK/DEF, can search (Mermail monsters) by discarding 1 card to the GY, then if she's destroyed (by battle or card effect) can send a Water monster from deck to GY and Special Summon 1 water monster from your GY in defense position (meaning no Links). Easy to make, good inclusion. [Link-2]

Marincess Coral Anemone - Coral allows for extending for the most part, since you can Special Summon 1 Water monster from your GY (with 1500 or less ATK), making it easy to get the ball rolling again. She locks you into Water monsters for the rest of the turn if you use her effect. [Link-2]

Bujinki Ahashima - The main use of Ahashima in this deck list is to go into Abyssgaios with more ease, which also allows you to not need to discard in order to special summon a level 7 from hand (in case you don't have enough materials to discard). [Link-2, requires 2 monsters with the same level]

Spells

Deep Sea Aria - An important searcher, banish 1 Water monster from your GY and search out any level 4 or lower Sea-Serpent, good for extending mostly.

Abyss-Scale of the Mizuchi - An equip card that you hope your opponent won't read, it allows you to negate any spell your opponent uses at resolution, and it doesn't activate, meaning you can swerve around cards you normally wouldn't be able to, like Super Polymerization, Dark Ruler No More, etc.

Frog Engine

Frog Plays - The frog engine does more for this deck than someone might think, yes being able to extend with Ronintoadin is nice, but being able to bounce a card back to your hand has some niche uses.

Ex:

1. Normal Summon 'Deep Sea Diva'

2. Special Summon 'Heavy Infantry' off of her effect (+1 Normal Summon)

3. Special Summon 'Swap Frog', send Ronintoadin to the GY

4. Bounce 'Deep Sea Diva' back to the hand

5. Normal Summon Diva again, Special Summon Neptabyss

6. Activate Neptabyss's effect, send Dragoons (search 1), add Dragoons to hand

Doing just that, you've managed:

1 level 2 Tuner

3 materials (Deep Sea Diva, Neptabyss, and Swap Frog) + extender in GY

2 free searches

Replacements/Additions

Atlantean Marksman - You won't really be using his 1st effect all that much (if he inflicts battle damage, 1400 ATK) you can Special Summon 1 level 4 or lower "Atlantean" monster from your deck. You might want him for his ability to destroy Set cards your opponent controls when he's sent to the GY (in order to activate a Water monster's effect). [Level 3] [Suggested amount of copies: 1-2]

Yamatako Orochi - Easily searchable/summonable Tuner that can be treated as either a level 1 or level 8 Tuner (if used for a Synchro summon), which can be put in for an easy level 10 Synchro. He's the best replacement for Moulinglacia in my opinion. [Level 1] [Tuner] [Suggested amount of copies: 1]

White Aura Whale - White Aura Whale can be a menace and a good addition for any Water deck, and with the deck having no real trouble making level 8 Synchros, shouldn't be an issue. To make this easier:

If Synchro summoned you can destroy all attack position monsters your opponent controls

Can make up to 2 attacks on your opponent's monsters during the battle phase

Does piercing

If destroyed by battle or card effect by your opponent, you can Special Summon it from your GY by banishing 1 Water monster, and it becomes a Tuner, allowing for recursion and potential Synchro plays.

Tatsunoko - A level 3 Synchro that allows you to use 1 monster in your hand as Synchro material, which with the amount of level 7s you might have in hand and can search, makes going into your level 10s a lot easier. [Level 3] [Tuner]

Abyss Shark - You'll be using this solely for extending and to help with deck thinning, since if all you control are Water monsters, you can Special Summon him and search out Abysspike. [Level 5] [Suggested amount of copies: 1-2]

Fishborg Launcher - Fishborg, while a good card, can be a soft garnet, since it does allow you to summon itself from the GY, you have to only have Water monsters in your GY (meaning Maxx "C" and Ash Blossom can ruin it). That being said, he can make going into your level 8 Synchros a bit easier. [Level 1] [Tuner] [Suggested amount of copies: 1]

Source: https://steamcommunity.com/sharedfiles/filedetails/?id=2964013160

Guide to Mermail/Atlanteans