In the sport of MMA, fighters are always looking for a way to gain an edge during the fight, and sometimes that can lead to negative things like TRT but it can also lead to innovation. There are a lot of moves that are underutilized in MMA which could give any fighter the edge in the cage, and these are, in my opinion, the top five moves they could be used more by any fighter.
#5 Elbows from the Clinch
Many fighters are known to use the clinch to throw knees or dirty box, but they are missing the elbows that could be thrown from there. Your hand and your knee are potentially more delicate and prone to injuries than your elbow. You can break noses, cut open the face, or even knock someone out with this move. Just look at Ricardo Lamas who became the only man to finish Erik Koch with this technique.
#4 Foot Stomps
Matt Serra was infamous for this move, but it makes you wonder why no one else uses it. How much time is spent against the fence with two fighters just hugging? The least you could do is stomp on there foot, and while this may be a move left over from the dark ages of MMA, it is still legal. In the end, stomping the foot will limit mobility, make a fighter hesitant, and open them up for a punch to the face.
#3 Knees to the Body(on the ground)
This move is probably not used as much due to fighters being worried about delivering an illegal blow, but with pinpoint accuracy you can finish a fight and leave your opponent lying on the ground. One of the last times GSP finished a fight was when he took Matt Serra out with knees to the body, but fighters like Rashad Evans, Anderson Silva, and Abel Trujillo have stopped fights with this technique as well.
#2 The Omoplata
The lone submission on this list is here because of the multitude of things it opens up. You can use the omoplata to sweep, transfer to an armbar, to a triangle, or even finish the fight. This makes it one of the more versatile moves in the sport. Another big advantage to it is that your opponent cannot punch you when you have them in it, because the way your bodies are contorted you could actually hit them without worrying about retaliation.
#1 Punches to the Body
How many times have you seen a fighter try to wail away on a fighter when they are hurt but totally ignore that their body is open to punches? For me it is too many times. It has been seen how devastating punches to the body can be when used by fighters like Cub Swanson, Junior Dos Santos, and Chad Mendes. While a shot to the body will not knock your opponent out cold, it will more often than not drop them to the ground and take away their wind. Also, even just punching to the body makes them wary of it, and will open them up to the knockout punch on the chin as well. It only makes sense to use it, but somehow most fighters have not figured that out.