In the blink of the mind's eye, Ryouta Sakamoto suddenly finds himself transported from playing the hit Btooom! video game to being stranded on a mysterious island, equipped with a day's worth of provisions, a bag of bombs, a strange crystal embedded in his left hand and a huge gaping hole in his memory. But it doesn't take long to figure out what's going on, especially after the first person Ryouta meets tries to kill him. (myanimelist.net)