u/TJ_sixtyfour

Max score means achieving the maximum score in a mission.

That means completing the mission's main objective(s), completing the mission's optional objective(s), earning a perfect combat bonus of 10.00, earning a perfect time bonus of 5.00, and turning on the 5 skulls that grant bonus skull points. And playing on legendary.

There is one mission where it's impossible to do all that, and it's not Arcadia City.

Side-by-side comparisons of the endings of the original Xbox 360 & Definitive Edition versions.

And I threw in a few other things as well, such as the one-time Flynn is playable in the 360 version.

The Patty reference in the 360 version.

The Coliseum dialogue difference in 100 or 200 Man Melee in the 360 & D.E.

Three different fights of Yuri vs. Duke on Unknown difficulty, soloing, without using any items, and without taking any damage. In the original Xbox 360 version and the Definitive Edition version.
One from the 360 version and two from the Definitive Edition version.

First fight, the original Xbox 360 version
In the original 360 version, bosses were much easier to lock down into combos compared to the Definitive Edition.

First Definitive Edition fight: The One Hit Kill Method
Vesperia No.2 + Overlimit lvl4 + Combination 1,2 & 3 skills + then do 3 normal attacks, then basic, then arcane, then 3 normal attacks, then basic, then altered, then arcane, then finally hold down the arte and attack buttons at the same time = Overkill

Second Definitive Edition fight: Hard Way
The non-one-hit-kill method
He's very different from his 360 version as he techs out a lot.