Kingdom Hearts Chain of Memories
This will probably be one of the more controversial placements on this list, but this is my party and I’ll stan Chain of Memories if I want to. Chain of Memories, the Game Boy Advance deck-building game, set the standard for what Kingdom Hearts would become. Sora’s trek through Castle Oblivion is the first spin-off and establishes that every Kingdom Hearts game would matter in the long run. Kingdom Hearts II’s opening hours make zero sense if you haven’t played Chain of Memories, and even after it’s made its own introductions, so much of the sequel (and the franchise at large) is building off of it nearly 20 years later. The Riku route you unlock after beating the game? A cultural reset.
On top of setting the tone for the rest of the franchise, Chain of Memories is an incredibly underrated deck builder. The cards you have inform your combos, abilities, and strategies within an action game framework that was pretty impressive for the GBA. Its sprite work is still gorgeous to this day, and god, I wish the original was more readily available. Chain of Memories was remade for the PlayStation 2 as Re: Chain of Memories, which does away with the 2D style for something that resembles the original game on console. That’s the version that has been ported to every system under the sun, and it is, in my opinion, far inferior. Sure, it’s got voice acting and some mechanical tweaks, but it’s not the same, dammit.