ocean of terror deck (YGO)

[Mewtwoisabeast]

ok this water deck is based off the new structure deck with some additions.

2x Ocean dragon lord-Neo daedalus
8 star 2900/1600 sea serpand/effect
send "umi" on your side of the feild to the graveyardto send all
cards in boath players hands and on the feild to the graveyard exept
this card.
2x levia dragon-Daedalus
3x mobius the frost monarch
1x Terrorking Salmon
2x 7 colored fish
2x Sea serpant Warrior of darkness
1x aqua spirit
1x mermaid knight
1x Amphibiouse bugroth mk-3
3x unshaven angler
2x mother grizzly
2x nightmare penguin
1x penguin soldier
2x star boy

spell cards
3x A legendary ocean
2x umi
1x pot of greed
1x reload
1x Mystical space typhoon
1x Snatch steal
1x hammer shot
1x premature burial
1x heavy storm
2x terraforming

trap cards
1x spell sheild type-8
2x torrential tribute
1x draining sheild
1x call of the haunted
1x tornado wall
1x bottomless trap hole

now thats the water deck i put Neo daedalus's effect up because im not sure how many people know it yet. And in case you want to know about the fire structure decks main guy here is infernal flame emporor.

Infernal flame emperor
9 star 2700/1600
pyro/effect
This card cannot be special summoned. When this card is tribute summoned successfully. You can remove from play up to 5 fire monsters in your graveyard. Destroy a number of spell or trap cards on the feild equal to the number of cards that you removed from play by this effect.

[PrimeCupEevee]

(In now way am I a professional deckbuilder. I'm just trying to help others.)

I don't know if you know or not, but Neo Dragon was already errata'd before release to match its Japanese version card. You now have to tribute a Levia Dragon from your side of the Field in order to Special Summon it. Also, it is a Nomi monster, which means that it can't be brought back from the Graveyard directly to the Field in any way, shape, or form. That might change your deck around right now before I give you a chance to amend it.

Your goal seems to make this a Beatdown/WATER deck, so I'll change the deck to that. I'm also assuming you don't have the really rare cards, but I'll add in common powerful ones you should be able to trade for.

Five Tributes even under ALO is too high; I can see why you want several Mobii in there, as you have no other S/T removal, but I'll take care of that as well. Also, there is a common WATER monster called Gagagigo from DCR. It got 1850 ATK and four stars, so it's slightly better than your 7 Colored Fish and Sea Serpent Warrior. In addition, there's a 5-star monster common from IOC called Giga Gagagigo, with 2450 ATK, so I'm replacing the one Salmon and add another Giga, since ALO should be on the field. Three Unshaven Anglers sounds like overkill, since you're only going to have 2 monsters you can tribute them for; I'm taking one out. To provide versatility, I'm going to throw in another Mother Grizzly. Even in the worst case scenario, it can search another copy of itself, thus stalling for you. The Mermaid Knight and Bugroth really don't mesh well with this kind of deck; I'll take them out. Also, add Sinister Serpent and TIV. He should be used in almost every deck. Also, 2 Nightmare Penguin should be enough; so the soldier is going out.
-2 Mobius
-2 7-Colored Fish
-2 Sea Serpent Warrior of Darkness
+3 Gagagigo
-1 Terrorking Salmon
+2 Giga Gagagigo
-1 Unshaven Angler
+1 Mother Grizzly
+1 Sinister Serpent
+1 Tribe-Infecting Virus
-1 Penguin Soldier

The Umis sound like overkill. If you have Terraforming, you'll most likely never search an Umi (usually you should take ALO). You're missing Graceful Charity, and that's common, so I'll add that. There's a common Spell from IOC called Salvage which allows you to take two WATER monsters from your grave and add them to your hand, so I'll add about two. The Reload just promotes bad hand advantage; I really don't like it. Since you have a lot of Beatsticks with high ATK power, I'll add some Noblemen of Crossout in.
-2 Umi
+1 Graceful Charity
+2 Salvage
+2 Nobleman of Crossout

Torrential Tribute is limited, so one automatically has to come out. You need S/T removal and S/T protection, so I'm going to have to add 2 Dust Tornado and 2 Magic Drain (Magic Jammer just promotes bad hand disadvantage in the game these days; so does Spell Shield). Even if ALO goes, your opponent has to get rid of at least two cards to do it. Draining Shield shouldn't be bothered with, since you should have the highest ATK power monsters.
-1 Torrential Tribute
+2 Dust Tornado
+2 Magic Drain
-1 Spell Shield Type-8
-1 Draining Shield

Try this overall deck:
Monsters: (21)
2 Neo Deadalus
2 Levia Dragon
1 Mobius
2 Giga Gagagigo
3 Gagagigo
1 Aqua Spirit
2 Unshaven Angler
3 Mother Grizzly
2 Nightmare Penguin
2 Star Boy
1 Sinister Serpent
1 Tribe-Infecting Virus

Spells: (16)
3 ALO
1 Pot of Greed
1 Graceful Charity
1 MST
1 Snatch Steal
1 Premature Burial
1 Hammer Shot
2 Salvage
2 Nobleman of Crossout
2 Terraforming

Traps: (7)
1 Torrential Tribute
2 Dust Tornado
2 Magic Drain
1 Call of the Haunted
1 Bottomless Trap Hole

Try that and see how it works.

[Latios Master]

One good thing to do is try to get as close to 40 cards as you can. Also, you should have just one Neo Daedalus because it is harder to get onto the field. Every water deck I've seen since Neo Daedalus came out only used one.