I Accidentally Picked up an Island

Picked up a blue crab. Picked up a beached shark. Not only can you catch the sea on the island, but you can also fish. If you want to build a breeding farm. Until one day, you picked up a monster corpse. You find that things are not that simple. You start building defenses. Solve the shelter, power supply, weapons, reconnaissance equipment in order, and then... This novel and its characters are purely fictitious. Any similarity is purely coincidental and should not be imitated.