public void increaseExp() {
	int e;
	if (level >= 1 && level <= 7) {
	    e = Randomizer.nextInt(10) + 15;
	} else if (level >= 8 && level <= 15) {
	    e = Randomizer.nextInt(13) + 15 / 2;
	} else if (level >= 16 && level <= 24) {
	    e = Randomizer.nextInt(23) + 18 / 2;
	} else {
	    e = Randomizer.nextInt(28) + 25 / 2;
	}
	setExp(exp + e);
    }