Nothing - hence why I don't call it a remake.
Well too bad, I just looked it up, and it's considered a full on remake. A one-to-one remake.
Buy Advance Wars™ 1+2: Re-Boot Camp and shop other great Nintendo products online at the official My Nintendo Store.
www.nintendo.com
Unleash your superior strategy skills and take on the baddies in this all-new spin on the beloved strategy series. This remake features two campaigns that cover the events of Advance Wars and Advance Wars 2: Black Hole Rising!
en.m.wikipedia.org
0 Advance Wars 1+2: Re-Boot Camp is a remake of Advance Wars and Advance Wars 2: Black Hole Rising, and the fifth game in the Advance Wars Series of games. It is also the first Advance Wars game to release on the Nintendo Switch platform, and in a departure from previous installments, it is...
advancewars.fandom.com
The key differences between Re-Boot Camp and the original games are the new art style, re-recorded soundtrack, the use of 3D graphics, and the addition of online versus functionality.
Re-Boot Camp contains the full campaigns of Advance Wars and Black Hole Rising.
Plus, I wouldn't consider something like this a remaster, when it's no longer pixel graphics and everything is using polygons and hand drawn animation for the character portraits. Those are all completely new assets made. A remaster is usually something that's ported over and it's usually upresed for HD. Or if it is already in HD, then a game is either given better frame rate or slightly better visual fidelity, if the game is already good looking to begin with. If this was really a remaster, everything would still be pixels. I know the lines have been blurred between remasters and remakes (some are exactly one to one and others are completely new or different games), but this is clearly a full-on remake that is done one to one. The only difference is that the first two games are made as one package. Similar to
Oneechanbara Origin. If it doesn't count your little category, too bad, it's a full-on regular remake of a pixel game using polygons instead. I know you at this point, and you have these weird stances that make no sense and are contradictory, so I'm not doing this back and forth. And don't even start with that agree to disagree nonsense either. You got a problem? I really don't care. Take your complaints to Nintendo, and they will send them to Don't Give a Damn Island.