With the addition of new cards such as Beautunaful and Fish Depth Charge, Mako Tsunami becomes more viable again. This might help Players who is a fan of FISH type decks to increase the competitiveness of their decks.
Your key card in this deck is Hammer Shark. Summon it as soon as possible to gain immediate control of the field. It's a 1900 beater along with the field spell card Umi, it gives access to your other monsters to be special summoned in the field.
Uminotaurus on the other hand is a great addition to this deck. Another 1900 beater along with the field spell card Umi. All of your monsters will benefit from its effect since the Monster Types in this deck is composed of Fish, Sea Serpent and Aqua-Type. It lets those types of monsters to deal damage even if your opponent's monster is in defense position.
You can summon a Hammer Shark and activate its ability to special summon Beautunaful, this can then be banished to search for other low level fish type monsters, and in a Hammer Shark deck, you will have plenty of options to summon. Alternatively, you can banish Beautunaful to summon another Hammer Shark and activate the second Hammer Shark's ability to special summon another monster from your hand, giving you 3 monsters in a turn.
Since Hammer Shark can special summon another monster, you can use the other monster to be tributed so it will not leave you defenseless, and will give you an extra draw as well.
You can also pressure your opponent by putting Yomi Ship in face up attack position and crash it with their monster. This might force them to use their back row if they do not want their monster to be destroyed.
If your opponent has two monsters on the field, activate the second effect of Enemy Controller to your Needle Sunfish. Take control of your opponent's monster with lower attack and use Needle Sunfish effect on the other one.
Boost and removal
Activate Hammer Shark's effect if possible, summon/special summon Lost Blue Breaker and use its effect to destroy your opponent's back row. Once you cleared your opponent's back row, your attacks now can not be interrupted, unless they have a Sphere Kuriboh on hand.
Even if your field spell Umi is destroyed, it can be compensated with the effect of Star Boy. Get over the attack of your opponent's monsters by summoning/special summoning Star Boy to buff up the attack of all your monsters. Hammer Shark's attack can go up to 2,400 with Star Boy and Umi on your side of the field.
Other useful cards
For versatile cards which can be used in any deck, check the link below.
Activate this card if you do not have a Hammer Shark, or if there are other cards that you need. Just make sure that you have enough monsters to defend your field, since you will be shuffling back two water monsters from your hand to your deck.
Activate this card to prevent your monsters on the field from getting destroyed by card effects for three turns. This card also serves as distraction for your field spell card to be destroyed since your opponent might be forced to target this card instead of Umi.
Actually, yes it is. Of course, Floodgate is a pain to deal with, but you can reach KOG with the right techs. I reached it, teching AMA and Paralel Twister. Of course, it isn't a top tier deck, but is very balanced and consistent, reaching The highest rank with some effort.
Your win condition is either field control using Daedalus or having a large number of beater monsters in play. I'd focus more on Uminotaurus/Hammershark than on support cards like Starboy. Starboy is pretty easy for your opponent to pick off doing damage to you in the process. Better to rely on Umi/Legendary Ocean for your damage boost.
Try to stick to 20 cards. The extra 1 from Shard of Greed actually hurts you some just having the extra card (think my math on the changes above was a little off...) For this deck, I'd prefer "Moray of Greed" anyways as it has better synergy with your deck.
I like my Hammershark deck quite a bit too, it's the first competitive deck I built. It makes me sad that they do so poorly in the meta now.
Lmao. What if ppl want to farm wins in ranked for 100 wins in plat/gold for easy wins?
Even now, I still think this is a good budget deck, I find that I have trouble beating Pheonix Decks and Red Eyes are 50/50 (usually weather or not its Zombie or Vanilla) and Cyber Angels is probably going to be way better (fought one so far and lost). But even so it still got me into Plat 4 so far.
2 Yomi and Sunfishes are probably not necessary for this deck. I'm only running one of each.
I also like to run one Deep Sweeper and one Lost Blue. Although the Deep Sweeper can't be special summoned by Hammer Shark, unless you have Legendary Ocean, it can be special summoned by Beatunaful Princess. So if you need spell/trap removal you can special summon Princess with Hammer and then summon Sweeper from your deck. And since it's fish type you can use it with Fish Depth Charge (although I don't have mine yet so I don't know how often I'd use it on Sweeper).
Oyster Meister can also be a useful alternative. He's lvl 3 so he can be summoned by Hammer and he's fish type. His effect can also come in handy. If you tribute him with Depth Charge or Econ the token he summons can be useful. I've used it for stalling or use it for another Econ tribute.
Overall it's a fun deck, good in PVE and PVP. And since it's mostly level 4 or lower monsters the chances of bad hands are not as frequent as some other decks. But with new meta coming I don't expect this to make it into KOG again like it did for some others.
Update! Made it to Legend 2 with this deck. I'm still of the opinion that REZD and CA are better, but this deck still held up alright. I've done my 100 wins so I'm probably going to stop doing ranked duels and not attempt to get KOG since I'm pretty tired of fighting nothing but Cyber Angels and Red Eyes.
You can win against CA easily if you have only one Econ in your starting hand. Summon a monster. Let your opponent summon Dakini. Activate Econ when Dakini's effect is activated. Take control of Dakini and you'll have to destroy Dakini thanks to her own effect. Hammershark is not the best deck ever, but one of the more versatile. REZD can't win against anti-Meta deck. With Hammershark deck, you do
Very Bad Deck u Will Never reach King of Games. Its Tier 2 of Even 3 Deck. But Never Tier 1
I reached KOG with this deck with small modification and my own touch to counter Cyber angels. Legend1 to KOG without losing a game. 68 wins to reach KOG. I started with Cyber angels then Phoenix then I tried REZ and nothing worked for me.
KOG with this deck (slightly modified too) during the last two seasons. Right now, I'm Legend 2 in less than 40 wins. It's one of the more versatile deck. Last season, I struggled to reach KOG with my REZD deck but then I switched to this one and ranked up easier. Tier 1, 8.5/10
Got into legend 2 last season with hammer shark. Got 65 wins in 10 days, been to lazy to play more, ran thru platinum with 3 losses to Red eyes, in legend lost to psychics
I am running a version of this deck,even though i have a Phoenix and a REZD deck,i have been reaching KOG pretty easily with my Hammer Sharks.It is one of the best decks,it can counter really well Toon decks,Naturia is shit anyways.The only one that gives me problems is that shit of REBD due to CV but stil it's ok.