The Sahelanthropus in Mission 31 are very difficult to defeat in Metal Gear Solid V: The Phantom Pain. Really? Many have tried of beating the Sahelanthropus, but they find it extremely difficult. So to clear the difficulty check this guide below which will help you defeat him with ease and also how to get an S-Rank in this Mission in MGS V: The Phantom Pain.
How To Beat Sahelanthropus
Before you start the mission make sure you have your preparations done. You need an assault uniform(with armor), drum grenade launcher, RPG torch, the horse or d-walker, Partner if required. Do not get too close to him, stay far away from the protuberances on the ground. Try to hide them as far as possible to attack him from behind.
As the battle begins, start with the grenade at his stomach. Avoid the supply drops from the beginning and use it only when you are out of ammo or RPGs are enough. Start aiming at the tanks on his back, here the point is to run him out of health and he will start flying towards the rock to hide. As he is tired and weak start hitting him on the belly and he will be defeated.
How to get S-Rank
As you know that this will be going to be a fight against the boss(Sahelanthropus), so you need a rocket launcher and a Grenade Launcher(GNOM-11 and Isado RGL-220 respectively). Empty your grenade launcher as when you use up one weapon's ammo you a supply drop will be triggered automatically. You need to Keep the rocket launcher handy and pick up the ammo as it will be available. Now keep repeating this strategy and you will defeat the boss with ease.
Hint: The Sahelanthropus weak spots are his belly and his upper back, keep hitting those.