for (i = 0; i < argument3; i += 1)
{
    bone = instance_create(900, 900, obj_bonewall);
    bone.y = global.idealborder[3] - argument0;
    bone.hspeed = argument1;
    bone.x = 320 - (argument2 * argument1);
    if (bone.x < 320)
        bone.x -= i * 15;
    if (bone.x > 320)
        bone.x += i * 15;
}