Fish

Fish monsters used to be one of the least supported types in the game, if not the absolute least. Recently, however, Tactical Evolution, Phantom Darkness, The Duelist Genesis and Crimson Crisis Sets have released some new Fish that make using them a potent strategy. Most noteworthy Fish monsters have effects that require the presence or tribute of other Fish to activate.

The idea of the improved fish deck is to summon Superancient Deepsea King Coelacanth by tributing Unshaven Angler or any other way (Mausoleum of the Emperor, Big Wave Small Wave and Star Blast), using his effect to summon 2 Royal Swamp Eel and 2 Oyster Meister (Or other fish cards). Then Synchro Summoning the fish cards as required to form Dark Strike Fighter and another Synchro, or Tribute Summoning Earthbound Immortal Chacu Challhua the next turn. Fish Depth Charge, Spiritual Water Art - Aoi, Abyssal Kingshark and, of course Superancient Deepsea King Coelacanth all help the deck.

Some of the better Fish monsters include: "Cranium Fish", "Earthbound Immortal Chacu Challhua", "Abyssal Kingshark", "Superancient Deepsea King Coelacanth", "Golden Flying Fish ", "Unshaven Angler", "Oyster Meister", and "Royal Swamp Eel".

Playing Style
The additions of the Tactical Evolution, Phantom Darkness, and The Duelist Genesis packs have given much needed support to make Fish a viable deck option.

The idea of this deck is to Summon Superancient Deepsea King Coelacanth with either a standard Tribute Summon, the effect of Unshaven Angler, or Big Wave Small Wave. You can then use his effect to summon Monsters that can be used as Tributes for Summons, Spiritual Water Art - Aoi, or Fish Depth Charge. For example, you can Summon Oyster Meister, use it for Spiritual Water Art - Aoi and use its token for Fish Depth Charge. Or you can use Deepsea Macrotrema to give your other Fish a power boost for that turn (yes these are legitimate combos as the effects of Oyster Meister and Deepsea Macrotrema activate in the Graveyard). Finally, you can summon Ocean's Keeper to Tribute for Thousand-Eyes Jellyfish (which I strongly suggest against) or Cranium Fish (a very awesome card to incorporate, regardless of the use of Ocean's Keeper). Another type of deck is the Fish OTK, which consists of getting Superancient Deepsea King Coelacanth on the field as quick as possible. From there, you can bring out up to 2 Level 8 Synchros (Special Summon 2 Royal Swamp Eel and 2 other lvl 4 non-tuner fish), and then, you can attack for game.

A few cards to take note of:

Superancient Deepsea King Coelacanth - The heavy hitter of this deck, the strongest fish monster to date, able to flood the field with fodder, and cannot be targeted as long as other fish are on the field. This card can be used to do a multitude of different things, as mentioned below, and should be included in any fish deck.

A Legendary Ocean - This make Superancient Deepsea King Coelacanth require only 1 Tribute to Summon. You can also Summon Terrorking Salmon without a Tribute, which it will then be able to destroy the popular Stardust Dragon (which can really mess with Fish Depth Charge) by battle. The power boost is also slightly helpful.

Levia-Dragon - Daedalus - While not a Fish monster, if you use A Legendary Ocean, you can use this as a back-up plan.

Umiiruka - Another Field Spell available. This one is solely for power boosts, however.

Cyber Shark - You can't Summon this with Superancient Deepsea King Coelacanth, but he'll be really easy to Summon with his help. You don't require a Tribute to Normal Summon him if a Water Monster exists on your side of the field. Just note that the effect of Superancient Deepsea King Coelacanth forces you to fill as many Monster Card Zones as possible. Also, do not use this card with A Legendary Ocean, as otherwise you would be better off using Terrorking Salmon.

Cranium Fish - Possibly even more threatening than Superancient Deepsea King Coelacanth. Discard a Water Monster to destroy a Face-down card! This gives you no fear of Bottomless Trap Hole for summoning your other Fish, or Mirror Force when you attack.

Abyssal Kingshark - Try not to summon this one with the effect of Superancient Deepsea King Coelacanth. Its effect will be very helpful if you accidentally run into a Torrential Tribute or Mirror Force, as he won't be destroyed (works once per turn)! You can also combo this with Levia-Dragon - Daedalus to clear the field, except two monsters you can use for direct attacks.

Golden Flying Fish - Feels left out, being a Light attribute monster. Essentially you have the Hand of the Six Samurai for Fish monsters. In fact, it's even more deadly here, to the point where if this and Superancient Deepsea King Coelacanth are both on the field simultaneously, except when Golden Flying Fish is summoned by the Coelacanth's effect, you pretty much win.

Royal Swamp Eel - New card given to us from Crimson Crisis. Superancient Deepsea King Coelacanth's effect can summon two of these and two other level 4 fish, and voila! 2 level 8 Synchros! Of course there are other combos you can do with this, like 2 Deepsea Macrotremas for a Brionac with +1000 attack for the turn *ouch*

Salvage - Used best with Cranium Fish. You literally supply him with ammo when you use this card. Just be sure you have a good number of Fish with 1500 ATK or less.

Pot of Avarice - To repeatedly use Superancient Deepsea King Coelacanth's effect effectively, you can use this to recycle used Fish, then summon them again to counter the deck fattening!

Monster Cards

 * Superancient Deepsea King Coelacanth
 * Shark Cruiser
 * Cranium Fish
 * Terrorking Salmon (if using A Legendary Ocean)
 * Cyber Shark (if not using A Legendary Ocean)
 * Earthbound Immortal Chacu Challhua
 * Ocean's Keeper
 * Deepsea Macrotrema
 * Abyssal Kingshark
 * Golden Flying Fish
 * Royal Swamp Eel (if you wish to use Synchros)
 * Oyster Meister
 * Unshaven Angler
 * 7 Colored Fish
 * Metabo-Shark
 * Unshaven Angler
 * Thousand-Eyes Jellyfish

Spell Cards

 * A Legendary Ocean
 * Umiiruka (optional/if not using A Legendary Ocean; you can even use both)
 * Mausoleum of the Emperor (this can be helpful for summoning Superancient Deepsea King Coelacanth... other stuff too but this is probably the main one)
 * Terraforming (if using Umiiruka or Mausoleum of the Emperor)
 * Big Wave Small Wave
 * Pot of Avarice
 * Salvage
 * My Body as a Shield (this can be used for extra protection)
 * Star Blast This card enables a normal summon of Superancient Deepsea King Coelacanth really fast. Besides, allows you to Synchro with Royal Swamp Eel, and enabling the effects of the fishes summoned.
 * Hydro Pressure Cannon
 * Water Hazard

Trap Cards

 * Spiritual Water Art - Aoi
 * Fish Depth Charge
 * Tornado Wall (if using A Legendary Ocean)
 * Dust Tornado
 * Mind Crush (dependent on how many copies of Spiritual Water Art - Aoi is being run; you can also use or Thousand-Eyes Jellyfish to make this card more potent)
 * Aegis of the Ocean Dragon Lord

Other Options
Ice Master - Summoning a mass of Water monsters for a discard makes summoning her easy. Her low attack for a level 8 and lack of synergy with the rest of the deck otherwise is why it is difficult to recommend using her.

Giga Gagagigo - Stronger than Terrorking Salmon by 50 ATK. However, it is a Reptile making him harder to fit into the deck, as he is not compatible with the various types of support run, such as Fish Depth Charge.