Fugu

Fugu, the Frightening is the fourth boss in the game Donkey Kong Country: Tropical Freeze and its Nintendo Switch port. He is the boss of Sea Breeze Cove, appearing in the level Fugu Face-Off. Before the battle, the Kongs meet Fugu while he is small. After the Kongs make fun of his size, Fugu bloats up and the battle commences. He is named after the pufferfish.

Physical description
Fugu is a very round, yellow pufferfish with blue stripes on his back and proportionately small blue fins that are wrapped in metal bands, making them resemble ponytails. His only garment is a large, blue bib around his neck with the Snowmad insignia on it. Fugu's eyes are large and angled with thick blue eyebrows, and his mouth is full of sharp teeth and lined with thick reddish lips, with a blue soul patch beneath it. At first, his relative size appears to be rather small, roughly the size of Donkey Kong himself. However, upon being startled, his size increases immensely, and fluctuates numerous times throughout the battle, even growing large enough to take up half of the arena. Like most pufferfish, Fugu has tiny red spikes that erect only when he inflates himself, and cover his entire body except for the patch of skin around his tail, leaving him open to attacks from behind. With each phase during his boss fight, Fugu develops reddish lines along his body, which turn darker with time.

Attacks
Fugu attacks by attempting to inhale the Kongs, exhaling water to push them into the sides of the arena, which are covered with spikes. Fugu is capable of creating strong currents by inhaling or exhaling water, which respectively increases and decreases his size. While Fugu is larger, he can corner his opponents to compensate for his slow swimming-speed. By exhaling water, Fugu can also aim the current in any direction and even use it to spin around and move around arena. His stomach has many Sea Urchins and green fish, which he can spit out and send many of them at the Kongs. Fugu's backside is his vulnerable spot, because it does not have spines to protect it. The Kongs can also knock the green fish sent out by Fugu back at him, causing him to deflate and be vulnerable to attack from any angle.

Combat
To defeat Fugu, the Kongs will have to damage him nine times by several means, which include ramming into his backside while he is bloated, ramming a green fish into him, or by hitting him while he is deflated.

Trivia

 * Fugu is the second pufferfish that serves as a boss in the Donkey Kong franchise, the first being Puftoss. Incidentally, both bosses are also fought in the fourth world of their respective games.
 * Fugu is the only boss character in Donkey Kong Country: Tropical Freeze and its Nintendo Switch port who has his name in the English level title.
 * Whenever Donkey Kong gets hit while Fugu is enlarged, Fugu will break the fourth wall by looking at the screen and chuckling.

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