What are the differences between the difficulty levels?

I'm currently starting a New Game at 'Warrior' (hardest) difficulty level. I previously finished the game at 'Survivor' (normal) difficulty.

What should I expect?

Specifically:

• How do the enemies get harder?
  • Do enemy NPCs or creatures increase, or will their numbers stay the same?
  • Or will enemy NPCs and animals just have more hit points or deal more damage? Know by how much they are increased from normal difficulty? (You could also give an estimate. e.g. How many shots to kill a certain animal with a certain gun in normal difficulty, compared to in 'Warrior' (hardest) difficulty.)
    
• What are the differences with the stealth mechanics? Will they detect me easier?
• Any enemy AI behavior changes for the NPCs or animals? Do they become 'smarter'?
• Any other differences between the difficulty levels?

Feel free to give partial answers if you only know of the differences between the difficulty levels on a certain aspect of the game

Their numbers are constant: same 2-man patrols but enemies nearby will come to reinforce them quickly if they are within earshot and hear fighting. They will not have more hit points, but they will deal more damage in the sense that you take more damage. Warrior mode allows for 2 shots before you lose a health bar.

The bad guys will detect you more easily, and they will be smarter about where to look if they know something is going on.

Yeah, they become smarter. But this is mostly about group behaviour. For example, when I was playing on Warrior difficulty level, I crashed into a ditch near Amanaki at X:416.3, Y:771.6. I ran down a pirate, but another 2 gusy about 100 meters away came to investigate the crash, and before I knew it, I was fighting 7 guys that had me severely outgunned. Bad guys will use clearing methods such as grenades, and they will come after you from a great distance provided that they did catch sight of you. I will say that Warrior difficulty forces you to think smarter and interact more with the environment than you have before.

No of Outposts and equipments are same in all levels. Difference is that you get detected more quickly if you are not careful. You will need to be more alert and play with stealth as you might do in real world. damage from bullet or animal bite increases in higher level. no. of enemies at outpost are also increased.