Difficulty
Shadow of the Tomb Raider has listened to the fan feedback and changed the way you play. In a news blog on the Square Enix had defined the difference on how to play Shadow of the Tomb Raider.
In the previous games, Lara was equipped with her survival skills. When used the surrounding area would highlight points of interest e.g. enemies, tombs and animals. There would also be pasty white paint on surfaces that could be climbed on.
This was forwarded to Rise of the Tomb Raider (2015, Square Enix), but it became a controversy within the gaming world. Fans alike complained that it made the game too easy. In 1996's Tomb Raider there was no such as aide.
A time in existence where to get help on a game you had to dial a specialist number, players wanted the simplicity gone. Within the first reveal of Shadow of the Tomb Raider fans picked up that yet again the survival tatics and white marks where still included.
Now Sqaure Enix has gone above and beyond and now allowing the player to decide and customise the game to their standard. Taken from the Square Enix Blog post here's the difference in gameplay:
Combat
Easy
Aim assist enabled
Enemies have lower health and do less damage
Ammunition boxes are plentiful
Enemies have illuminated silhouettes
Normal
Enemies have normal health and damage
Ammunition boxes are rare
Enemies have illuminated silhouettes
Hard
Enemies have increased health, do more damage and locate Lara more quickly.
No health regeneration in combat
Ammunition boxes are rare
No hit markers on the reticle
Enemies are not highlighted in Survival Instincts
Deadly Obsession
Same as hard
No HUD icon when Lara is being detected by an enemy
Exploration
Easy
Obvious white paint on critical path
Longer saving grab timer
Base camps are lit
Normal
Discreet white paint on critical path
Normal saving grab timer
Base camps are unlit
Hard
No white paint on critical path
Reduced saving grab timer
No Survival Instincts during exploration
Base camps are unlit
Deadly Obsession
Same as Hard
Base camps are unlit and require resources to light
Game only saves at Base camps
Puzzles
Easy
Lara gives direct hints on next action to perform
Interactable objects are highlighted in Survival Instincts
Objects necessary to progress highlighted in blue during Survival Instincts
Longer window of opportunity for timed mechanics
Normal
Lara gives general hints on the next action to perform
Interactable objects are highlighted in Survival Instincts
Normal window of opportunity for timed mechanics
Hard/Deadly Obsession
No hints are given by Lara
No Survival Instincts
Shorter window of opportunity for timer mechanics