difficulty selection

[Cross 1]

In the beginning of the game it let's you select difficulty, Casual, Normal, Intense. but later you can talk to a guy Luck that changes it to be easy or harder what do these thing change exactly

[Gastronely 92]

Mostly changes trainer AI, levels, battle formats and some Pokemon on difficult battles, like the Gym Leaders, for example

[keyblade336 23]

Changes how hard you want the game to punch you in the face
Serious note though, as what above says
Harder AI's - They predict moves and counter you more

Some Leaders instead go Double battles to mess with you more with their field effects

Boss characters either have more pokemon or higher leveled or stated mons

[Liroy 11]

If you have time do it in intense mode, show the game who is the boss.

If you are just playing for the story go for casual mode.

[SnorlaxLove 1]

Almost finished my intense file. Definitely helps to have knowledge on which Pokémon are physical or special attackers and physical or special walls. Didn’t find the gym battles that overwhelming to be honest except for the bug type leader. No idea why but my team struggled against him. 
 

most frustrating thing you’ll notice is some of the AI know your every move. Might as well make the electric type leader a psychic. Knows every move/abilities of your Pokémon and if you switch he will attack with moves to counter the Pokémon coming in not the one that was switched out. Can’t remember the fight but if you used a priority move to finish one of their Pokémon off they would heal and if you tried to set up instead they wouldn’t heal and attack like wtf. 
 

I enjoyed intense though since it made me use Pokémon I probably wouldn’t or haven’t used at all. 

[Daniel Prithvi 9]

2 hours ago, SnorlaxLove said:

Almost finished my intense file. Definitely helps to have knowledge on which Pokémon are physical or special attackers and physical or special walls. Didn’t find the gym battles that overwhelming to be honest except for the bug type leader. No idea why but my team struggled against him. 
 

most frustrating thing you’ll notice is some of the AI know your every move. Might as well make the electric type leader a psychic. Knows every move/abilities of your Pokémon and if you switch he will attack with moves to counter the Pokémon coming in not the one that was switched out. Can’t remember the fight but if you used a priority move to finish one of their Pokémon off they would heal and if you tried to set up instead they wouldn’t heal and attack like wtf. 
 

I enjoyed intense though since it made me use Pokémon I probably wouldn’t or haven’t used at all. 

 Have to agree with you on that man. I used pokemons I never dreamt of using before in my life.

[Cross 1]

I think I'm just bad at the game then, I struggled against several gym leaders and some important battles on normal mode and it just got exhausting at points so I quit playing.