if I complete the game but don't have 20 trophies,can I continue playing the game 'til I get the amount of trophies and then redo the ending??and will be unlocked??

also since you can change the difficulty anytime you want can you play in beggininer for example all the game and just beat the final boss with critical or proud to get the trophy "beat the game on proud","beat the game on critical"?

Yes you continue playing the game. You unlock stuff after completing the game.

 

No you can't get the Proud or Critical trophies unless you're on one of those modes.

Yes you continue playing the game. You unlock stuff after completing the game.

 

No you can't get the Proud or Critical trophies unless you're on one of those modes.

 

I mean..after I complete the game and get 20 trophies will the secret ending be unlocked if I beat the final boss again??

 

but what if I'm on this mode just on the final boss??

I mean..after I complete the game and get 20 trophies will the secret ending be unlocked if I beat the final boss again??

 

but what if I'm on this mode just on the final boss??

 

Get the required number of trophies and a new cutscene appears in your library or whatever they call it. No replay of the final world is necessary.