Giant Sea Beast Girl Defense Hits Steam: Whale Girl vs Kaiju in 2027

Pico Games' new tower defense game Giant Sea Beast Girl Defense is coming to Steam in 2027, pitting a giant orca girl with battleship cannons against waves of monsters.
Ever wondered what it'd be like to command a giant whale girl with battleship cannons strapped to her hair clip? Yeah, us too. And apparently, so did Japanese solo developer Pico Games โ because that's exactly what their newly announced Steam title, Giant Sea Beast Girl Defense, is all about.
The game's hook is simple but wild: it's a giant girl versus giant monsters showdown. You team up with Orca, humanity's one and only ally โ a massive sea beast girl โ and use modern military firepower to hold off wave after wave of monsters storming in from the ocean. Your job? Protect what's left of humanity's living space.
The backstory sets things in an alternate world where, decades ago, giant creatures called "Kaiju" came crashing in from outer space and pushed the globe to the brink of extinction. Eventually, humanity discovered a new type of monster they could actually communicate with. After some investigation, they confirmed these beings were mammals โ and gave them the name "Sea Beast Girls." One of them, Orca, is a mutated killer whale who fights alongside human navigator Amano Iruka.
So how does the tower defense actually play? Orca is huge, but only her head pokes above the ocean surface during combat. Her hair clip is packing serious heat โ it's mounted with powerful battleship cannons. You'll need to move her head up and down to adjust your firing angle, aim at incoming monsters in the distance, and keep blasting away. With enemies arriving in overwhelming numbers, you can also call in battleships and local forces for supporting fire.
Each stage is split into several phases. It kicks off with the "Sea Surface Phase," where you use Orca's cannons to block monster hordes and hold the line while taking constant hits. Clear that, and you move into the "Undersea Phase" โ now you're piloting a submarine, diving to the ocean floor within a time limit to salvage materials from defeated monster remains. Those materials go toward upgrading Orca's equipment and cannons. But time is tight, and how efficiently you grab resources and power up could decide whether you survive the next fight.
At the end of each stage comes the big one โ the titular giant battle. Orca goes head-to-head with a "Giant Sea Beast Girl" boss packing multiple attack options. You'll need to lean on all the gear, shields, and firepower you've built up, plus master your cannon angles, to take down a boss on your own scale. Defeated bosses get dragged back to base for a research phase, where you study their body structure and internal condition, then use what you learn to upgrade your military equipment and boost humanity's odds against the monsters.
Pico Games has a solid track record too โ they previously released well-received titles like Abyss Kitchen, Doll Explorer, and Witch Explorer. Giant Sea Beast Girl Defense is set to launch on Steam in 2027, and it'll support Traditional Chinese interface and subtitles. So if giant whale girls with naval guns sound like your kind of chaos, you might want to smash that wishlist button now.
What do you think โ is this the weirdest tower defense concept you've seen lately? Will you be picking this up in 2027?
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