Compare it with a real giant:
Iran doesn't need outsiders (Americans in Jordan) to train rebel groups, just because they can't do it themselves. Iran has its Revolutionary Guards for this task. Iran doesn't need foreign military support in order to supply its proxies elsewhere, unlike KSA who has turned to Croatia and other states to secure this. Iran doesn't need US approval to step in when it thinks its interests are threatened. Iran, unlike KSA, doesn't just pour weapons into a area in order to increase its influence. Iran actually trains, forms, guide and orders its associates in a professional way. Iran doesn't need an alliance of various countries to realize its objectives in the region, unlike KSA, who needed Turkey, Egypt, Jordan and France to step up against Iran.
Like I said; KSA is far form being a giant.