(Most of my complaints in this post are issues I have fighting when playing Legendary and Mythic Warzone Firefight or playing the Campaign on Legendary)
Engagements
Knights: The Knights are very versatile and can engage you at any range, at long range they have near pin point accuracy with their light rifles and in Warzone firefight they seem to have pin point accuracy with their incineration cannons as well. When you engage the knights at close range they can charge you and take you out with their sword arm. They can also if they are too far away jump like 50 meters into the air and then slam onto you killing you instantly. Their armour has so much health they feel like the largest bullet sponge in the galaxy and even when their armour falls off they still have an insane amount of armour on the front. So ultimately the only effective way to kill them is to shoot from long range which gets very repetitive and tedious quickly. When you fight an elite, you know that once that shield is down a single headshot should do the trick. When the armour of a Knights breaks, its still a tank and requires so many shots to kill.
Soldiers: Soldiers at short to medium ranges are so lethal you can’t even respond to them once they begin firing. They are very lethal because they also seem to have hyper-lethal accuracy with their light rifles. What makes matters worse is that some of the promethean weaponry in Halo 5 have bullet tracking, so the user doesn’t even need to aim. They teleport around way too often, soldiers can sometimes use those little teleportation bursts they do like 15 times in a row. Them teleporting also makes it seem like an enemy just seemingly came out of nowhere and just shot you in the back even thought there was nothing there a second ago. It makes the player feel annoyed as they couldn’t do anything to prevent that soldier from teleporting. Maybe add a mechanic to when you either do enough damage or shoot something off the soldier, it disables its teleporting abiliy. Besides the sniper soldiers, they also seem to have a very high amount of health which makes them coupled with their lethality up close, insanely annoying to fight up close. Again making your only option for engaging them long range which becomes boring.
Crawlers: Crawlers are just grunts that can only be killed quickly with headshots. I have no idea why the rest of their body has so much health but not the head. You think that they would put more armour on the head seeing as its the most important thing in the machine but I digress. Many of the problems with the crawlers are the same as the Soldiers. Since they have auto tracking bullets with their boltshots, if you are fighting a large pack of them in an outside area it is almost impossible to dodge all their shots. They also rush you with their auto-aim guns. Sure the forerunners are very advanced so they probably invented auto tacking bullets, I mean even humans today have that technology but lore shouldn’t affect the gameplay in a way that detracts from the experience.
The Feel (Bunch of gripes with them I just put into one paragraph)
For me at least, killing a promethean doesn’t feel like an accomplishment, it feels more like a tedious chore that you had just completed. When shooting them, it doesn’t feel as if you are killing an enemy but instead it feels as if you are shooting a piece of metal. They’re robots, killing them doesn’t give me the same feeling as when i’m killing a living, breathing alien. When fighting the Covenant, you have so many ways to kill the units, you can get up close and personal with the Grunts, Jackals, Elites and use a wide plethora of methods to kill them with each of them making you feel satisfied and proud that you just pulled that off. Sometimes when running over soldiers you just bounce off. As I mentioned before, when you are shooting an elite you know once that shield gets down you’re good, with a knight, his armour could go down but then he’ll jump and slam into you with his sword. Even the sounds they make can get annoying too. When the knights laugh or lose an armour piece it just sounds like a bunch of screeches. How come the Soldiers which are just AIs can talk english but the Knights which are composed humans can’t? Also, the lack of Soldier lines in the game makes it so it feels as if they are broken records. I can’t tell you how many times I’ve heard a soldier ask himself if “this is humanities best?”. At first hearing them say something like “Forerunners defeated humans once, we will do it again” was cool, I was like “Oh wow they actually mentioned that during combat”. But now it just feels like i’ve heard it a hundred times, because I have. When a warzone firefight match goes ahead and puts 2 or 3 rounds or prometheans in a row I just sigh. Fighting the Covenant for me is just way more satisfying.