Someone could explain me how the f&ck I do the bone gun attack because I can't beat it without taking at least 50 damage
It is a bit tricky, but try not to move diagonally. Instead, look where it shoots and just hold one direction to get away. (W,A,S, or D) Switch to another direction after every shot. After that, just avoid the circle explosions.
i think he meant the garf-gun atack