Oh mercy, the silent moment in the very beginning had this little exchange of offscreen dialogue added to it:
Nene: "Where's Mikey and Shoutmon?"
Shoutmon: "Ugh! I'm underneath Ballistamon!"
Ballistamon: "Oops, my bad."
Along with this changed dialogue:
Shoutmon: "Aw no, we both squished Mikey. Mikey, wake up."
Mikey: *coughs and groans as he strains to get up*
Nene (in a silly, cheerful demeanor): "You poor thing. Flattened like a bug."
The shot of Taiki/Mikey sitting up and asking where they all are is zoomed in to hide a close up of Nene's legs and skirt from view.
Jigoku/Hell is renamed the Underworld.
Kiriha (in his own way) telling Taiki not to worry about their current predicament is changed to Christopher (in his own way) complementing Mikey on how he usually has a way of overcoming things when things look bad.
The Monitamon telling the others that the whole castle is empty is changed to them telling the others that there's a throne room at the top.
Shoutmon makes more stair-climbing complaints.
A shot of Christopher telling Shoutmon that he's not the Digimon King yet is inserted into the scene during Shoutmon's enjoying his sitting on the throne.
As Ewan appears before the Fusion Fighters in the castle, an offscreen disgruntled Shoutmon can be heard saying "Aw great. Shoulda known Mister Shortpants was behind this!" This newly-added clashes with the surprised reaction from everyone that comes a second later since Shoutmon is included among the surprised reactions, and his face in that shot does not match up at all with the disgruntled tone of his offscreen dialogue.
Hell's Field is renamed the Digital Underworld.
Ewan claims this place to be "the birthplace of all evil."
Okay, the scene with Blastmon, the Evilmons/Vilemons, and Lilithmon/Laylamon is really messed up in the dub. Originally, Blastmon was nervous about the forthcoming final battle, while in the dub he's complaining about being sent to the Underworld by Bagra to watch some humans battle since "the Underworld's a dump. The food is terrible and there's never anyplace to sit." (And is it just me or does Blastmon's dub voice sound different?) The Evilmons originally wanted to leave because they feared the pain that would come from their being manipulated by Yuu, only to get pulled back by Lilithmon's whip. In the dub, however, they figure that they're just going to get the snot beat out of them and so decide to leave "before Laylamon gets here," when we just saw her standing right next to them in a previous shot a few seconds ago. And Lilithmon's whip pulling them back when they try to leave is cut out, as is the whole bit of her playing with her breasts as she takes in how exciting this place is to her.
The terms "Boss" and "Leader General" are omitted from the dub, with Ewan instead saying that each team must defeat the other team's "General", leading to Christopher to instead ask which one since the Fusion Fighters have more than one General.
The dub is really going out of its way to avoid the subject of human death being a thing, which in a way kinda helps to justify Ewan's misbelief about death not existing in the Digital World. So... thanks for feeding into his delusions, dubbers?
Kiriha's line of "There is no 'never' in that! Miracles beyond your imagination can occur. I will teach you that!" is changed to Christopher's line of "This is not a game, it's real battle with real consequences. And one of us is not gonna survive it!"
Kiriha had already decided to take command in this battle from the start, while Christopher doesn't decide to step up and take over until after Mikey protests Christopher's saying that Ewan needs to be crushed in order to understand what's at stake here.
Axeknightmon (whose name is still spelled like that in the caption) refers to his troops as soldiers of the "Bagra Empire" instead of the "Bagra Army".
Maden is renamed the Dark Nest.
The red sea of death is changed to being pits of boiling lava.
Yuu originally informed his troops that communications do not work in Hell's Field, while Ewan does not, instead simply telling everyone that there will be no chance to regroup on the field.
Yuu also simply said that he's analyzed the personalities of the enemy in battles from afar, while Ewan specifically states that he's spent YEARS studying the enemy. Yes, YEARS.
WHAT?! Axeknightmon refers to his team as "Team TWILIGHT", when it has been known as "Team MIDNIGHT" all this time up until now in the dub.
The shot of DarkKnightmon and Gattai Lilithmon leading their army visible within Xros Heart's castle crystal is cut out.
Team Twilight's troops being referred to as "god's beasts" is changed to "divine beasts".
Laylamon Combined has her Vilemon faces removed from her body in the dub.
The shot of Shoutmon X5 landing his foot on the ground in front of DarkKnightmon's forces is cut out and replaced with a close up shot of DarkKnightmon. This shot was taken out since Gattai Lilithmon was in the shot as well.
X5, Beelzemon, and Mervamon all use and call out attacks in the dub, while they did not in the original. X5 uses "Earth Shaker" (but which is not captioned in the dub), Beelzemon uses "Oblivion Cannon" (given a caption in the dub), and Mervamon uses "Medullia Punch" (given a caption in the dub).
The shot of Beelzemon getting whacked to the ground by Blastmon is zoomed in to obscure Lilithmon from view.
The upward panning view of Gattai Lilithmon as Beelzebumon notices her aura being stronger than ever is cut out.
Laylamon commands some fire to fly upward with "Flame spires!" It wasn't an attack in the original, and is given no caption here either.
Wisemon originally explained the nature of Hell's Field and how it's the opposite of human Hell, being a place of evil empowerment instead of a place of punishment for sinners. In the dub, however, Wisemon says he has no data on the Underworld, and only senses that the Underworld is the opposite of the Digital World, being a place where evil flourishes and those with good hearts have almost no chance against those whose hearts have turned black.
The dub makes up two new attacks for Axeknightmon (though, no captions are given for them): "Electro Lance" and "Lava Lasso".
As Tuwarmon explains how all three of the Fusion Fighter's Generals' forces are to be defeated, the shot of Nene's forces being beaten by Laylamon is cut out.
Tuwarmon originally asked if Yuu was really okay with the idea of taking Taiki's life, while here he instead asks if Ewan understands that he has to destroy Mikey or it be "the end of you."
Oh, for crying out loud! Ewan actually get to say "And, I'll always have my memories of this amazing place, where no one ever DIES and no one ever gets hurt." After all that beating around the bush earlier they just come out and say the word "dies" like it was nothing! What gives, dub?!
Also, the "memories" line replaced Yuu's original line about the Digital World being a dream world.
Tuwarmon's original line to Tyutyumon about how he's grown fond of Yuu but needs to stay cool about this is changed to Tuwarmon saying to Tyutyumon "What do you expect me to say? That if he loses he turns to digital dust? I guess I could tell him that. Wow, this job is hard." Thus, the dub changed Tyutyumon from being Tuwarmon's little devil on his shoulder to being his little angel on his shoulder, since Tyutyumon was originally irked by Tuwarmon getting soft on Yuu while now he's instead irked by Tuwarmon contenting to let Ewan go on thinking what he does about the Digital World.
A shot of Ewan saying that he kinda misses being back home before having his attention taken back to the fight is inserted right after Tuwarmon's little conversation with Tyutyumon. This new shot doesn't make any sense since Ewan should not want to go back home at all.
The dub makes up an attack for Laylamon called "Flame Spires" where she throws a spiral of fire at Beelzemon and Mervamon. This is given a caption in the dub as well.
A shot of Beelzebumon shielding Mervamon from the fire as it scorches them both is cut out.
"Twin Spear" is renamed "Spinning Spear"
Axeknightmon makes it crystal clear to the audience that X5 has been stalling all this time, rather than it only being implied like in the original.
The Gorimon (which were unnamed in the original) are renamed as "Gorillamon"
Kiriha originally gave Greymon and MailBirdramon the simple command of "Into Taiki's Xros Loader!" Christopher, however, uses a new dub-coined term of "Fusion Loader Transfer".
Kiriha told Taiki to go clear Yuu's misconceptions and Taiki's own doubts, while Christopher tells Mikey that it's hard for Christopher to admit but it'll make them all stronger.
DarkKnightmon originally got unwillingly pulled down into the sea of death by X5, while Axeknightmon goes down into the lava with X5 on purpose. In other words, it was X5 who originally said "We're going for a swim!", while here it's Axeknightmon who says so instead.
"Mega Flame" is kept, not changed into "Nova Blast".
A shot of Lilithmon fleeing as blasts fired from Beelzebumon shoot past her is cut out.
As the scene cuts over to whispered, some offscreen dialogue from Laylamon is heard saying "No thanks, you keep it!" (as a response to Beelzemon's onscreen line telling her he's got a present for her).
the close up shot of Taiki's arm bleeding is cut out.
Ewan speaks of taking Mikey's character out and Mikey vanishing. Again, he got to say the word "dies" earlier, so what gives?
Valkyrimon is kept
Warrior is kept
"Fenrir Sword" is renamed "Feral Sword" (consistent with past Bandai of America Digimon media)
"Auvandil no Ya" is not renamed, but replaced with "Laser Javelin". The BoA name of "Auvandil no Ya" is "Lightning Arrow"
Mikey says Valkyrimon's armor can regenerate fallen heroes, and the bird companion Freyr is renamed "Flare".