• you want to take a deep breath because by far this game is the hardest legendary ive come so far(H2 Left to conquer)
  
• Second, beware of the truth and reconciliation level that one is the hardest
  

Right, here comes the actual guide
Im going to be compiled in this guide, not going to detail by detail in each level just in general basically

Classic indeed, noob combo they say but if it necessary to accomplish this very hard campaign in the most hard series its acceptable
and incase your dont know is plasma charge from the plasma pistol to an armored enemies(Elites, Brutes maybe) then hit its head with an headshot weapon(In CE is your magnum pistol it is) or you can use your sniper rifle.

the way the halo levels, all halo levels actually work is not always by completing it. you can skip few level if you can just by avoiding the crossfire and through an uncrowded crowd path. This one is a THING to the Flood

yes, I know its sound ridiculous. but hey if you hear me yes precision in this game is more working than firepower, like seriously yeah.

Try to be patience with the flood in their overwhelming number and horde. Plus they got weapon(Shotgun and zookas are annoying the most)

Now if you reached the level where the monitor takes you to halo *key? through flood horde, then ive got some tips.
here my tip :
In the very beginning where you spawn you'll see two high blocks in front of you, you want to grenade jumps onto that and grenade jump on to the next so you can skip that section entirely because its so hard
you want to trigger the monitor to go first actually because otherwise it wont work no enemy will spawn

1. Truth & Reconciliation
   
2. Two Betrayals
   
3. Keyes
   
4. The rest is the same

Here my Screenshots why this game is hard ;

Well, thats my guide in general Good Bye