The hardcore war / Winter Morgan.

Enhanced descriptions from Syndetics:

Noah and Violet, treasure hunters and protectors of the Overworld, are back in this sixth and final installment of the League of Griefers series. Someone has changed the environment from survival to hardcore. Now if you get destroyed, you can't respawn. Noah and Violet must find a way to get the world back to survival while fighting off another griefer war staged by the evil Daniel and his band of Rainbow Griefers.

There's no room for error in this battle against time. With Creepers lurking in the dark and teleporting Endermen appearing out of nowhere, the duo have a lot more on their hands than only Griefers. They must use all their knowledge and skills to fight off nearly every kind of mob known to Minecrafters.

Can they stop the Griefers and restore the world to the way it was before they get destroyed? Find out in this thrilling sixth and final installment of the League of Griefers series!

This adventure series is created especially for readers who love the fight of good vs. evil, magical academies like Hogwarts in the Harry Potter saga, and games like Minecraft, Terraria, and Pokemon GO.

Sky Pony Press, with our Good Books, Racehorse and Arcade imprints, is proud to publish a broad range of books for young readers--picture books for small children, chapter books, books for middle grade readers, and novels for young adults. Our list includes bestsellers for children who love to play Minecraft; stories told with LEGO bricks; books that teach lessons about tolerance, patience, and the environment, and much more. While not every title we publish becomes a New York Times bestseller or a national bestseller, we are committed to books on subjects that are sometimes overlooked and to authors whose work might not otherwise find a home.